Concentrations, bioaccumulation, and human health risk assessment of organochlorine pesticides and heavy metals in edible fish from Wuhan, China

Heavy Metal Levels and Cancer Risk Assessments of the Commercial Denis, Sparus aurata Collected from Bardawil Lake and Private Fish Farm Waters as a Cultured Source, Egypt

Heavy metal pollution of natural and cultivated habitats may be caused by agricultural, industrial, and human activities. Fish living in these habitats easily accumulate metals in their organs; for food safety and human health, the heavy metals in fish flesh are of major concern due to the harmful nature of these pollutants even in low quantities. In this study, metals (Iron, Fe; Lead, Pb; Cadmium, Cd; Nickel, Ni; Copper, Cu and Zinc, Zn) in the muscle, liver, intestine, and gill of gilthead seabream (Sparus aurata, Denis is local name) were monitored to determine the contamination levels and to investigate the protective impact of cooking methods on the reduction or mitigation of metal levels. Although the Denis samples exhibited relatively low Pb and Cd levels, most fish samples had elevated levels of Fe and Zn. The examined metals accumulated at the highest level in the liver and gills compared to the other organs. Results showed that cooking methods had a considerable effect on concentrations of metals. However, the levels of metal in S. aurata from various sources were reduced significantly (P < 0.05) by frying, microwave, and grilling cooking, which was ordered in the following sequence as microwave cooking < grilling < frying. The consumption of Denis fish from different sources (wild and cultured) has no negative effects on health, according to a study of health hazards based on indices of carcinogenic and non-carcinogenic. The metal results indicated that different fish sources (wild and cultured) could be acceptable for human consumption. Data hypothesized a positive impact of awareness among the native community.

Bioaccumulation and health risk assessment of trace elements in Tilapia (Oreochromis mossambicus) from selected inland water bodies

The presence of toxic trace elements (TEs) has resulted in a worldwide deterioration in freshwater ecosystem quality. This study aimed to analyze the distribution of TEs, including chromium (Cr), nickel (Ni), arsenic (As), mercury (Hg), cadmium (Cd), and lead (Pb), in water, sediment, and organs of Tilapia (Oreochromis mossambicus) collected from selected inland water bodies in Tamil Nadu, India. The water samples exhibited a range of concentrations for TEs: Cr varied from 0.014 to 5.193 µg/L, Ni ranged from 0.283 to 11.133 µg/L, As ranged from 0.503 to 1.519 µg/L, Cd from 0.001 to 0.616 µg/L, and Pb ranged from non-detectable (ND) to 6.103 µg/L. The concentrations of TEs in sediment were found to vary within the following ranges: 5.259 to 32.621 mg/kg for Cr, 1.932 to 30.487 mg/kg for Ni, 0.129 to 0.563 mg/kg for As, 0.003 to 0.011 mg/kg for Cd, ND to 0.003 mg/kg for Hg, and 0.404 to 1.575 mg/kg for Pb. The study found that the accumulation pattern of TE in fishes across all selected areas was liver > bone > gill > muscle. The organs had TE concentrations of Cr (ND-0.769 mg/kg), Ni (ND-1.053 mg/kg), As (0.002-0.080 mg/kg), Pb (ND-0.411 mg/kg), and Hg (ND-0.067 mg/kg), which was below the maximum residual limit prescribed by EC and FSSAI. The bioconcentration factor (BCF) of TEs exhibited a greater magnitude in comparison with the biota-sediment accumulation factor due to the higher concentration of TEs in fish and lower level in water. The assessment of both carcinogenic and non-carcinogenic risks suggests that the consumption of Tilapia from the study region does not pose any significant risks.

Bioaccumulation of Potentially Toxic Elements in Commercially Important Food Fish Species from Lower Gangetic Stretch: Food Security and Human Health Risk Assessment

Ganga river is the inhabitant of more than 190 fish species and important river system of India. Potentially toxic elements (PTEs) in the Gangetic riverine ecosystem are a hot environmental issue. A detailed evaluation of PTEs bioaccumulation in Gangetic fishes is required to safeguard human health. The present study investigated the bioaccumulation of PTEs (Cd, Co, Cr, Cu, Li, Ni, Pb, Se, Zn, and Mn) within 12 economic fish species (n = 72) collected from the lower Gangetic stretch. The mean concentrations of PTEs followed the order Zn > Cu > Mn > Ni > Se > Cr > Pb > Co ~ Li > Cd. Li and Se bioaccumulation were studied first time from Gangetic fishes. Results demonstrated that all the selected PTEs were below the maximum permissible limit recommended by reference standards except for Zn in L. catla and L. rohita. For all PTEs, the metal pollution index (MPI), hazard quotient (THQ), and hazard index (HI) were < 1, indicating that these PTEs do not pose a health risk to the public through the dietary intake of fish in this study area. All studied fish were acceptable in terms of carcinogenic risk (CR) from exposure to Cd, Cr, and Pb. Multivariate statistical analysis suggests that inter-correlated metals have similar dispersion properties and bioaccumulation homology within the body. This study provides a scientific basis for food safety assessment and continuous monitoring of PTEs in Gangetic fishes is suggested in the future to safeguard human health.

Strategies for mitigation of pesticides from the environment through alternative approaches: A review of recent developments and future prospects

Chemical-based peticides are having negative impacts on both the healths of human beings and plants as well. The World Health Organisation (WHO), reported that each year, >25 million individuals in poor nations are having acute pesticide poisoning cases along with 20,000 fatal injuries at global level. Normally, only ∼0.1% of the pesticide reaches to the intended targets, and rest amount is expected to come into the food chain/environment for a longer period of time. Therefore, it is crucial to reduce the amounts of pesticides present in the soil. Physical or chemical treatments are either expensive or incapable to do so. Hence, pesticide detoxification can be achieved through bioremediation/biotechnologies, including nano-based methodologies, integrated approaches etc. These are relatively affordable, efficient and environmentally sound methods. Therefore, alternate strategies like as advanced biotechnological tools like as CRISPR Cas system, RNAi and genetic engineering for development of insects and pest resistant plants which are directly involved in the development of disease- and pest-resistant plants and indirectly reduce the use of pesticides. Omics tools and multi omics approaches like metagenomics, genomics, transcriptomics, proteomics, and metabolomics for the efficient functional gene mining and their validation for bioremediation of pesticides also discussed from the literatures. Overall, the review focuses on the most recent advancements in bioremediation methods to lessen the effects of pesticides along with the role of microorganisms in pesticides elimination. Further, pesticide detection is also a big challenge which can be done by using HPLC, GC, SERS, and LSPR ELISA etc. which have also been described in this review.

Distribution, bioaccumulation, and health risk assessment of organochlorines across the riverine ecosystem of Punjab Province, Pakistan

This study was designed to assess the distribution of organochlorines (OCs) in fish species, their spatio-temporal variations, bioaccumulation potential, and associated human health risks via dietary intake. The levels of twenty-three organochlorine pesticides (OCPs) and thirty-five polychlorinated biphenyls (PCBs) were analyzed in six fish species collected from the riverine ecosystem of Punjab Province, Pakistan. The results indicated that the mean levels of Σ23OCPs were 74.1 ng/g ww and 184 ng/g ww, and for Σ35PCBs the levels were 38.8 ng/g ww and 74.8 ng/g ww in herbivorous and carnivorous fish species, respectively. The most abundant contaminants in all fish species were DDTs (65%) and HCHs (14%) among OCPs and heavier PCB congeners (62%) among PCBs. As for dioxin-like PCBs, the WHO toxic equivalency values (ng TEQ/g ww) were in the range of 0.21 (Cyprinus Carpio) to 2.38 (Rita Rita), exceeding the maximum allowable limit of 0.004 ng TEQ/g, ww by the European Commission. Spatio-temporal analysis indicated relatively higher OC levels in winter season with elevated concentrations in fish samples from industrial zone. The bioconcentration factor (L/kg) values ranged from 723 to 2773 for PCBs and 315 to 923 for OCPs in all fish species, with higher levels were reported in carnivorous species. The human health risk assessment at both 50th and 95th percentiles revealed the absence of any significant non-carcinogenic risk as calculated HR was less than 1. However, the critical carcinogenic risk was found to be associated for most of the contaminants, signifying the dietary exposure to OCPs and PCBs might pose the public health concern.

Human biomonitoring of heavy metals exposure in different age- and gender-groups based on fish consumption patterns in typical coastal cities of China

The study aimed to investigate heavy metals (HMs) concentrations in human hair based on fish consumption patterns in Qingdao, Xiamen, and Zhoushan. The (HMs) concentrations were determined using acid digestion and an inductively coupled plasma mass spectrometer (ICP-MS, NexION 300X, PerkinElmer). The associated health risks were investigated using risk assessment models described by the United States Environmental Protection Agency (USEPA). The order of fish HMs concentration in Qingdao was CdCrCu>Pb>Cr>As>Cd in all three study areas. The hair Zn concentration in 28 % of the studied population exceeded the safety standards. Overall, the hair HMs concentration was found to be high in middle-aged groups (19-45 and 45-59), and the hair HMs concentrations were high, especially in the case of females. A significant correlation was noticed between hair As (0.119; p < 0.05), Cr (0.231; p < 0.05),) and Cu (0.117; p < 0.05),) and fish consumption frequency. High Odd ratios (>2) were noticed for As, Cu and Zn in high fish-eating frequency. A significant non-carcinogenic risk was noticed in human Cr exposure (1.10E+00) in Xiamen, and the hazard index values indicated non-carcinogenic risk in Xiamen and Zhoushan. The carcinogenic risk for human As exposure (2.50E-05-7.09E-03) indicated a significant cancer risk.

Heavy metals in fish, rice, and human hair and health risk assessment in Wuhan city, central China

The current study investigated the concentration of heavy metals (HMs) in human hair associated with fish and rice consumption in Wuhan City, central China. The mean values of As in 8/10 fish species exceeded the food safety standard of 0.015 mg/kg. The mean values (mg/kg) of HMs in rice followed a descending order of Zn (13.7)> Cu (1.9)>Cr (0.51)>As (0.11) >Cd (0.08) >Pb (0.04). The ascending order of HMs for male hair was Cd < As < Cr < Pb < Cu < Zn, while As < Cd < Cr < Pb < Cu < Zn for female. 30% of hair Cr and 22% of hair Zn contents exceeded the recommended values. The middle age (19-44) and adult (45-59) groups were the most vulnerable group, as the concentration for most elements was high in these age groups. A significant correlation was found between fish-eating frequency and hair Zn (r = 0.213; p < 0.05), and As (r = 0.204; p < 0.05). High odd ratios were found in a population with high fish-eating frequency, especially for Pb (7.19), As (3.1), Zn (3.83), and Cd (3.7). A significant non-carcinogenic risk was associated with Cr exposure through consuming herbivores, filter feeders, and omnivorous fish. The cancer risk values of Cd exposure (1.54E-04) via rice consumption and As exposure (1.25E-04) via consumption of omnivores fish indicate precautionary measures.

Residues of carcinogenic pesticides in food: a systematic review

Most agricultural products are exposed to pesticides. Organochlorine (OCPs) insecticides have been banned for years due to their persistence in the environment and lipophilic properties. On the other hand, some carcinogenic organophosphates are used in high amounts. Therefore, this systematic review was performed with the keywords; pesticide, carcinogenic, carcinogen, residue, contamination, pollution, and food to determine the type of food and pesticide. 663 manuscripts were found by searching in databases. After initial screening and quality assessment of full text, 26 manuscripts were selected. In this study, by reviewing selected manuscripts, about 13 pesticides were associated with carcinogenic effects. These pesticides were Chlorothalonil, Glyphosate, Tetrachlorvinphos, Parathion, Malathion, Diazinon, heptachlor, Hexachlorobenzene, aldrin, dieldrin, DDT, chlordane, Lindane. Most of these pesticides were organochlorine. The organochlorine pesticides are primarily detected in foods of animal origin. In some studies, the amount of carcinogenic organochlorine was higher than the permissible levels. From the carcinogenic herbicide, Glyphosate. An important finding of this systematic review is that carcinogenic organochlorines are still a threat to cancer incidence.

Comprehensive GIS based risk surveillance of organochlorine pesticides (OCPs) in edible fish species of River Chenab, Pakistan

The present study was conducted to evaluate Carcinogenic (TR) and non-carcinogenic (THQ) human health risk of organochlorine pesticides (OCPs) in three edible fish species (Labeo boga, Channa marulius and Wallago attu) of River Chenab, Pakistan using USEPA human health risk assessment model. Holistic GIS (Geographic information system) based Geo-Statistical approach has been employed for the first time in River Chenab, Pakistan to categorize contaminated risk zones of OCPs based on single pollution index. The ∑OCPs concentrations in fish species were ranged from 5.09 to 414 ng/g with the prevalence of dieldrin. Results of single pollution index of DDE, aldrin, dieldrin and ∑endosulfan revealed River Chenab as polluted and risk zone area. Distribution pattern assessed significantly higher (p < 0.05) concentrations of OCPs in downstream area suggesting substantial pollution of surrounded industrial region. The human health risk assessment depicted no harmful non-carcinogenic (THQ) risk except for ΣOCPs concentration of C. marulius. Significant carcinogenic (TR) health risk exhibited by all examined OCPs from maximum of the studied sites. Therefore, the high carcinogenic human health risk had highlighted an immediate removal of continuous disposal of OCPs in the River Chenab.

Ecological and human health hazards; integrated risk assessment of organochlorine pesticides (OCPs) from the Chenab River, Pakistan

Carcinogenic hazards to human health were investigated through oral and dermal exposure to organochlorine pesticides (OCPs) from water samples (n = 120) of River Chenab, Pakistan. The Pioneering study aimed to employ an integrated geographic information system (GIS) based geostatistical method for the determination of pollution load by GC-ECD from water of River Chenab. The residual levels of OCPs detected from water samples ranged from 0.54 to 122 ng L^-1 with significant prevalence of DDE and α-HCH. Results of the Nemerrow pollution index (NeI), single pollution index (SPI), and comprehensive pollution index (CPI) reflected the downstream zone a stern pollution risk zone. The spatial distribution pattern through geostatistical approaches also revealed significantly higher (p < 0.05) OCP levels in the downstream zone. Risk quotient (RQ_CCC) of surface water quality with respect to heptachlor epitomized a high level of risk (RQ_CCC > 1). Non-carcinogenic human health risk (Σ HQ) assessment ranged from 8.39 × 10^-9 to 1.7 × 10^-3, which represented a marginal risk through oral and dermal exposure. However, carcinogenic risks by oral exposure route were ranged from 3.57 × 10^-11 to 4.46 × 10^-6. Estimated cancer risk (ΣCR) exhibited a considerable carcinogenic risk posed by heptachlor, α-HCH and dieldrin. It is suggested to employ an immediate mitigation strategy for the constant discharge of OCPs in the studied area.

Computational modeling of aquatic toxicity of polychlorinated naphthalenes (PCNs) employing 2D-QSAR and chemical read-across

Polychlorinated naphthalenes (PCNs) are produced from a variety of industrial sources, and they reach the aquatic ecosystems by the dry-wet deposition from the atmosphere and also by the drainage from the land surfaces. Then the PCNs can be transmitted through the food chain to humans and show toxic effects on different aquatic animals as well as humans. Considering this scenario, it is an obligatory task to explore the toxicity data of PCNs more deeply for the species of an aquatic ecosystem (green algae-Daphnia magna-fish), and to extrapolate those data for humans. But the toxicity data for different aquatic species are quite limited. The laboratory experimentations are complicated and ethically troublesome to fill toxicity data gaps; therefore, different in silico methods (e.g., QSAR, quantitative read-across predictions) are emerging as crucial ways to fill the data gaps and hazard assessments. In the present study, we developed individual toxicity models as well as interspecies models from the 75 PCN toxicity data against three aquatic species (green algae-Daphnia magna-fish) by employing easily interpretable 2D descriptors; these models were validated rigorously employing different globally accepted internal and external validation metrics. Then we interpreted the modelled descriptors mechanistically with the endpoint values for better understanding. And finally, we endeavored to improve the prediction quality in terms of external validation metrics by employing a novel quantitative read-across approach by pooling the descriptors from the developed individual QSAR models.

Comparative study on metal concentrations in water, sediments, and two fish species (Cyprinus carpio and Pelteobagrus fulvidraco) from the Wujiang River, China

In order to assess the metal pollution in the Wujiang River, concentrations of Cu, Zn, Fe, Mn, Pb, Cd, As, and Hg in the water, sediments, and two fish species Cyprinus carpio and Pelteobagrus fulvidraco from the middle reaches (Tuomugang, TMG) and lower reaches (Wulong, WL) of the Wujiang River were examined. The results indicated that all metal concentrations were lower than the values for grade one water quality according to the Environment Quality Standard for Surface Water of China (GB 3838-2002). The bioavailable fraction concentrations of Zn, Fe, Mn, Pb, and Hg in WL were significantly higher than those in TMG (p < 0.05), indicating that these metals in sediments of WL have higher bioavailability and mobility. The Cu, Zn, Fe, Pb, As, and Hg were mainly related to the residual fraction, while the Mn and Cd were mainly associated with the non-residual fraction. The risk assessment code (RAC) and the secondary phase to the primary phase (RSP) values indicated that Mn and Cd have a high risk of secondary release. The mean metal concentrations in the liver of the two fish species were higher than those in muscle. The higher metal concentrations of fish in WL suggested that bioaccumulation of metals in fish could be influenced by metal bioavailability. No identical relationships between metal concentrations and fish length were manifested in the present study. The values of target hazard quotient (THQ) and hazard index (HI), and carcinogenic risk (CR) of metals for the consumption of C. carpio and P. fulvidraco indicated that the anglers would likely not experience significant non-carcinogenic risk, but the carcinogenic risk of As cannot be ignored. Thanks to prohibited commercial fishing in the Wujiang River, the metal pollution will probably not pose a health risk to the general public for wild fish consumption.

Health risk-benefit assessment of the commercial red mangrove crab: Implications for a cultural delicacy

Mangrove forests, provide vital food resources and are an endangered ecosystem worldwide due to pollution and habitat destruction. A risk-benefit assessment (RBA) was performed on the red mangrove crab (Ucides occidentalis) from the threatened Guayas mangroves in Ecuador. It was aimed to assess the combined potential adverse and beneficial health impact associated with crab consumption and define a recommended safe intake (SI) to improve the diet of the Ecuadoran population while ensuring safe food intake. Target hazard quotients (THQs), benefit quotients (Qs), and benefit-risk quotients (BRQs) were calculated based on the concentrations of the analyzed contaminants (121 pesticide residues, 11 metal(loid)s, antimicrobial drugs from 3 classes) and nutrients (fatty acids, amino acids, and essential nutrients). Except for inorganic arsenic (iAs), the THQ was below 100 for all investigated contaminants, suggesting that the average crab consumer is exposed to levels that do not impose negative non-carcinogenic or carcinogenic health effects in the long and/or short term. Concentrations of iAs (average AsIII: 25.64 and AsV: 6.28 μg/kg fw) were of the highest concern because of the potential to cause negative health effects on long-term consumption. Despite the thriving aquaculture in the Guayas estuary, concentrations of residues of the antimicrobial drugs oxytetracycline (OTC), florfenicol, and nitrofurans still were low. Based on the fact that different risk reference values exist, related to different safety levels, four SI values (0.002, 0.04, 4, and 18 crabs/day) were obtained. The strictest intake values indicate a concern for current consumption habits. In conclusion, the red mangrove crab contains various important nutrients and can be part of a balanced diet for the Ecuadorian population when consumed in limited portions. The present study emphasizes the importance of safeguarding the quality of the environment as a prerequisite for procuring nutritious and safe food.

Metals bioaccumulation, possible sources and consumption risk assessment in five Sillaginid species, a case study: Bandar Abbas (Persian Gulf) and Chabahar Bay (Oman Sea), Iran

In this study, the concentrations of 10 metals (As, Al, Cd, Cr, Cu, Fe, Hg, Ni, Pb and Zn) in different tissues (gill, muscle and otolith) of five sillaginid species (Sillago arabica, S. attenuata and S. sihama from the Persian Gulf and S. indica, S. sihama and Sillaginopodys chondropus from the Oman Sea) were analyzed using ICP-MS, and the potential human health risk assessment for local consumers was also conducted using standard indices. The concentration of trace metals (μg g^-1 dw) in fish ranged from 0.24 to 16.09 (As), 7.88 to 167.51 (Al), 0.005 > -0.866 (Cd), 0.006 > -7.95 (Cr), 1.02-5.58 (Cu), 24.86 to 390.85 (Fe), 0.005 > -1.93 (Hg), 0.021 > -7.80 (Ni), 0.33-4.41 (Pb) and 4.78-170.43 (Zn). The levels of trace metals varied significantly among sampling sites, fish species and their tissues. Gill tissues accumulate higher concentrations of the analyzed elements, except for As and Hg, whose higher concentrations were found in muscle tissues. Among the species, S. sihama in the Persian Gulf showed the highest levels of toxic metals compared to the other species. The dendrogram of metal association in fish muscle tissues revealed that Ni, Cr, Cd, Pb and Hg in muscles mainly originated from anthropogenic sources, especially petroleum activities. A second dendrogram based on the association of these five metals in the muscle tissue separated the sillaginid species of the Persian Gulf from the Oman Sea. The mean concentrations of the analyzed metals in the edible tissues were lower than international standards of maximum permissible limits (MPL), except for inorganic As (_iAs) and Pb. The index of estimated daily intake (EDI) for Cr and Hg in all sillaginid species, and _iAs, Pb and Ni only in the Persian Gulf's sillaginid species was higher than the recommended values. The value of the target hazard quotient (THQ) indicated that the intake of individual heavy metals due to the consumption of sillaginid species was safe for human health (except Hg in S. arabica) whereas combined heavy metals' intake revealed potential health problems in the case of increased consumption for all three sillaginids in the Persian Gulf. Target cancer risk (TR) for _iAs in all species and Cd, Cr and Ni in Persian Gulf species was higher than the acceptable range. The results indicated the health issues associated with high consumption, especially for sillaginids in the Persian Gulf, which should be considered in food safety monitoring for local people in the area.

Health risk assessment of organochlorine pesticide residues in edible tissue of seafood

Fish is one of the most valuable foods with high-quality animal protein. However, aquaculture, or ingesting contaminated food, allows organochlorine pesticides (OCPs) to enter the fish's body, and therefore, it negatively impacted public health. One-hundred and twenty random samples of Clupea harengus (C. harengus), Mugil cephalus (M. cephalus), Sardinella aurita (S. aurita), Oreochromis niloticus (O. niloticus), Neptunus pelagicus (N. pelagicus) and Sepia savigngi (S. savigngi) (n = 20 each) were collected from local markets in Mansoura city, Egypt. Samples were checked to see whether any residues of OCPs with the application of risk assessment due to their consumption by Mansoura citizens. The findings indicated that summation hexachlorocyclohexane (∑HCH) in examined seafood samples ranged from 0.27 ± 0.13 in N. pelagicus to 61.61 ± 52.03 μg.kg-1 in S. aurita. Also, the γ-HCH isomer was considered the more prominent among isomers. Hexachlorobenzene (HCB) was found in five different species, with mean values of 2.03 ± 1.85, 1.5.7 ± 1.17, 0.94 ± 0.87, 0.35 ± 0.06, and 0.18 ± 0.06 μg.kg-1 in C. harengus, S. aurita, M. cephlaus, O. niloticus, and S. savigngi. Moreover, summation of Heptachlors (∑HPTs) was 10.19 ± 7.63, 1.27 ± 0.26, 2.58 ± 0.11, 0.95 ± 0.12, 0.21 ± 0.11 and 0.32 ± 0.03 μg.kg-1 of wet weight in examined C. harengus, M. cephlaus, S. aurita, O. niloticus, N. pelagicus, and S. savigngi. Aldrin and dieldrin residues were 3.75 ± 1.31 and 4.86 ± 1.33 μg.kg-1 in C. harengu, meanwhile they were 1.61 ± 0.77 and 0.78 ± 0.04 μg.kg-1in M. cephalus. Dichlorodiphenyldichloroethylene (pp-DDE) was dominant in all examined species within different concentrations 5.08 ± 4.12, 0.98 ± 0.10, 3.07 ± 0.91, 0.93 ± 0.27, 0.08 ± 0.01 and 0.35 ± 0.02 μg.kg-1 in C. harengus, M. cephlaus, S. aurita, O. niloticus, N. pelagicus and S. savigngi, respectively. We concluded that all examined seafood samples were lower than the recommended maximum residue limit. Also, the estimated daily intake was less than the permitted daily intake. Non-carcinogenic indices of target hazard quotient and hazard index for OCPs in all examined species were less than 1.

Modified DLLME-GC-TQMS determination of pesticide residues in Gomti River, Lucknow, India: ecological risk assessment and multivariate statistical approach

This research article aims to establish an easy and well-defined analytical method for detection and quantification of multiclass pesticides in Gomti river water samples because the increased agricultural activities, industrialization, and urbanization had increased the presence of pesticides in the ecosystem which causes the depletion of water quality making it a global concern. The analytical method, vortex-assisted ultrasonication-based dispersive liquid-liquid microextraction-solidification of floating organic droplets (VAUS-DLLME-SFO) was optimized using one parameter at a time approach which gave the recovery between 69.45 and 114.15%, limit of detection (LOD), and limit of quantification (LOQ) 0.0011-0.0111 µg/L and 0.0033-0.0368 µg/L, respectively, and RSD in the range of 0.75-1.29 which shows sensitivity and accuracy better than earlier reported methods. The data obtained were subjected to measurement uncertainty, risk assessment, and multivariate statistical analysis to establish the robustness of the developed analytical method. The measurement uncertainty found was concluded to be in the acceptable range for analytical results. Furthermore, the real samples were analyzed and the associated value of the risk quotient was found to be less than 1, except for aquatic invertebrates, establishing the fact that the current concentration of pesticides has no such negative threat to flora and fauna. The possible source of pesticides in the Gomti river system was established by multivariate analysis. It was thus concluded that anthropogenic activity is responsible for the variable concentration of pesticides found in the sample.

Exposure Routes and Health Risks Associated with Pesticide Application

Pesticides play an important role in agricultural development. However, pesticide application can result in both acute and chronic human toxicities, and the adverse effects of pesticides on the environment and human health remain a serious problem. There is therefore a need to discuss the application methods for pesticides, the routes of pesticide exposure, and the health risks posed by pesticide application. The health problems related to pesticide application and exposure in developing countries are of particular concern. The purpose of this paper is to provide scientific information for policymakers in order to allow the development of proper pesticide application technics and methods to minimize pesticide exposure and the adverse health effects on both applicators and communities. Studies indicate that there are four main pesticide application methods, including hydraulic spraying, backpack spraying, basal trunk spraying, and aerial spraying. Pesticide application methods are mainly selected by considering the habits of target pests, the characteristics of target sites, and the properties of pesticides. Humans are directly exposed to pesticides in occupational, agricultural, and household activities and are indirectly exposed to pesticides via environmental media, including air, water, soil, and food. Human exposure to pesticides occurs mainly through dermal, oral, and respiratory routes. People who are directly and/or indirectly exposed to pesticides may contract acute toxicity effects and chronic diseases. Although no segment of the general population is completely protected against exposure to pesticides and their potentially serious health effects, a disproportionate burden is shouldered by people in developing countries. Both deterministic and probabilistic human health risk assessments have their advantages and disadvantages and both types of methods should be comprehensively implemented in research on exposure and human health risk assessment. Equipment for appropriate pesticide application is important for application efficiency to minimize the loss of spray solution as well as reduce pesticide residuals in the environment and adverse human health effects due to over-spraying and residues. Policymakers should implement various useful measures, such as integrated pest management (IPM) laws that prohibit the use of pesticides with high risks and the development of a national implementation plan (NIP) to reduce the adverse effects of pesticides on the environment and on human health.

Effect of household culinary processes on organochlorine pesticide residues (OCPs) in the seafood (Penaeus vannamei) and its associated human health risk assessment: Our vision and future scope

Food safety is crucial in today's competitive trading market, as it directly affects human health and promotes seafood exports. The effects of thermal processing (boiling, frying, grilling, and microwave cooking) on pesticide residues (PR) in P. vannamei were assessed. The PR in raw and processed shrimp ranged from 0.007 to 0.703 μg/kg for uncooked/raw, not detected (ND) to 0.917 μg/kg for boiled, ND to 0.506 μg/kg for fried, ND to 0.573 μg/kg for grilled and ND to 0.514 μg/kg for microwave cooked shrimps. The Endrin, endosulfan sulfate, and heptachlor were predominant PR found in the raw and processed shrimp. The PR content in raw and cooked shrimps were below the maximum residue limits (MRL) set by the Codex Alimentarius Commission (2021) and the European Commission (86/363/1986 and 57/2007). The estimated daily intake (EDI) of PR from raw and processed shrimps were below the ADI prescribed by CAC. The hazard quotient (HQ) and hazard ratio (HR) values were <1, indicating no non-carcinogenic or carcinogenic health implications through shrimp consumption. The estimated maximum allowable shrimp consumption rate (CRlim) suggests an adult can eat >100 shrimp meals/month, which is over the USEPA's (2000)recommendation of >16 meals/month without health issues. The Effect of thermal processing was detected in the following order: boiling < grilling < frying < microwave cooking. The processing factor (PF < 0.7), paired t-test (t < 0.05), Tukey post hoc (p < 0.05) test, Bray-Curtis similarity index, and matrix plot exhibited that all the four thermal processing methods have a considerable impact on pesticides in the processed shrimps. But frying (59.4%) and microwave cooking (60.3%) reduced PR far beyond boiling (48.8%) and grilling (51.3%). Hence, we recommend frying and microwave processing are better methods for minimizing PR in seafood than boiling or grilling.

Potentially toxic elements contamination and its removal by aquatic weeds in the riverine system: A comparative approach

Thamirabarani river acquires large untreated sewage effluents from the Tirunelveli and Thoothukudi districts of South Tamil Nadu. This study examined the concentration of trace elements in water, sediment, and phytoaccumulation potential of aquatic weeds viz., A. cristata, E. crassipes, S. natans, and P. stratiotes, growing along Srivaikundam dam of Thamirabarani river. The Pb, As, Hg, Cd, and Ni concentrations in water were slightly higher than the US Food and Drug Administration (USFDA) drinking water guidelines; however, their accumulation in sediment was below WHO's sediment quality guideline. This study concludes that the phytoaccumulation factor (PAF) and translocation factor (TF) was >1 in E. crassipes and A. cristata, representing them as hyperaccumulators, suitable for phytoremediation in polluted localities. E. crassipes, A. cristata, and S. natans accumulated (100-500 fold) higher trace elements concentrations than that present in the water. Also, the concentrations of trace elements found in the aquatic weeds were below the recommended levels for the critical plant range (CRP). These selected aquatic weeds are more suitable for plant hybridization to be modified as superbug plants.

Fate of bis-(4-tert-butyl phenyl)-iodonium under photolithography relevant irradiation and the environmental risk properties of the formed photoproducts

Aryl-iodonium salts are utilized as photoacid generators (PAGs) in semiconductor photolithography and other photo-initiated manufacturing processes. Despite their utilization and suspected toxicity, the fate of these compounds within the perimeter of semiconductor fabrication plants is inadequately understood; the identification of photolithography products is still needed for a comprehensive environmental impact assessment. This study investigated the photolytic transformation of a representative iodonium PAG cation, bis-(4-tert-butyl phenyl)-iodonium, under conditions simulating industrial photolithography. Under 254-nm irradiation, bis-(4-tert-butyl phenyl)-iodonium reacted rapidly with a photolytic half-life of 39.2 s; different counter ions or solvents did not impact the degradation kinetics. At a semiconductor photolithography-relevant UV dosage of 25 mJ cm^-2, 33% of bis-(4-tert-butyl phenyl)-iodonium was estimated to be transformed. Six aromatic/hydrophobic photoproducts were identified utilizing a combination of HPLC-DAD and GC-MS. Selected photoproducts such as tert-butyl benzene and tert-butyl iodobenzene had remarkably higher acute microbial toxicity toward bacterium Aliivibrio fischeri compared to bis-(4-tert-butyl phenyl)-iodonium. Octanol-water partition coefficients estimated using the Estimation Programs Interface Suite™ indicated that the photoproducts were substantially more hydrophobic than the parent compound. The results fill a critical data gap hindering the environmental impact assessment of iodonium PAGs and provide clues on potential management strategies for both iodonium compounds and their photoproducts.

Probabilistic public health risks associated with pesticides and heavy metal exposure through consumption of common dried fish in coastal regions of Bangladesh

The chemical contaminants in dried fish are of great food safety concern and an emerging public health issue in Bangladesh. The aim of this study was to assess the public health risk associated with exposure to pesticides (organochlorine and organophosphorus) and heavy metals (lead, mercury, cadmium, chromium, arsenic) through the consumption of dried fish (Bombay duck, ribbon fish, silver jewfish, shrimp, Chinese promfret) in coastal districts (Cox's Bazar, Chittagong, Bhola, Patuakhali, Khulna) of Bangladesh. Dried fish consumption data were collected from 500 adult respondents (100 from each district) using a food frequency questionnaire (FFQ). Pesticide residues were determined using QuEChERS extraction coupled to gas chromatography and gas chromatography mass spectrometry, and heavy metals were estimated using an atomic absorption spectrophotometric method. The results revealed that the frequency and amount of dried fish consumption was highest for Bombay duck in Cox's Bazar (11.57 g/capita/day) and ribbon fish (12.10 g/capita/day) in Chittagong. The estimated daily intake (EDI, 7.40 × 10^-5 to 1.10 × 10^-4 mg/kg/day) and health risk index (HRI, 0.013 to 0.16) values expressed no health risk from pesticide residues in all the positive samples. For heavy metals, target hazard quotients (THQ) for non-carcinogenic health risk were below 1 (0.001-0.154), indicating no health risk for all samples. However, carcinogenic risk R value indicated a potential health risk for chromium (2.64 × 10^-6 to 4.06 × 10^-6), and carcinogenic R_T value (2.82 × 10^-6 to 5.71 × 10^-6) indicated a potential health risk for all the metals. It is concluded that the risk of exposure to pesticides through the consumption of dried fish is low, while heavy metals pose moderate-to-high health risks to dried fish consumers in the study area. Thus, the study suggests an appropriate risk management policy that controls pesticides and heavy metals in dried fish to ensure safe food for local and global consumers, underpinned by a producers' capacity building and consumers' awareness raising strategy.

Assessment of recombinant glutathione-S-transferase (HaGST-8) silica nano-conjugates for effective removal of pesticides

Diverse glutathione-S-transferases (GSTs) are produced by insect pests including Helicoverpa armigera (HaGSTs) for detoxification of insecticides or xenobiotic compounds that they encounter. In an earlier study, the HaGST-8 gene was isolated from H. armigera larvae exposed to pesticide mixtures and the recombinant protein was expressed in the yeast Pichia pastoris. In this investigation, HaGST-8 was successfully immobilized on glutaraldehyde-activated APTES functionalized silica nanoparticles to obtain SiAPT-HaGST-8 nano-conjugates. Although enzyme activity associated with these conjugates was comparable to that of free HaGST-8, the specific activity of the former was found to be 1.25 times higher than the latter. In comparison with the free enzyme (that demonstrated a pH optimum of 9.0), for the nano-conjugates, the pH range was extended between pH 8.0 to 9.0. The optimum temperature for activity of both forms of the enzyme was found to be 30 °C. Stability of the enzyme was improved from 20 d for free HaGST-8 to 30 d for SiAPT-HaGST-8 nano-conjugates. Some loss in GST activity was detected after every reuse cycle of nano-conjugates and in all, 63% reduction was observed after three cycles. When 3 kinds of pesticides (namely, chlorpyrifos, dichlorvos and cypermethrin) were reacted with SiAPT-HaGST-8, more than 80% reduction in levels were observed. On the basis of the results obtained, the use of such silica nanoparticle-based systems for stable enzyme conjugation followed by effective removal of pesticides from aqueous media is envisaged.

Monitoring of pesticides in surface water, pesticides removal efficiency in drinking water treatment plant and potential health risk to consumers using Monte Carlo simulation in Behbahan City, Iran

Excessive application of pesticides to control pests and weeds leads to contaminating bodies of water and health problems for consumers. The present study was designed to investigate the concentration of pesticides in raw water originated from the Marun River as well as the treated water of the drinking water treatment plant in Behbahan City. The efficiency of each treatment process was evaluated. Moreover, the health risks caused by detectable pesticides for consumers of treated water were assessed. The target pollutants were extracted using droplet liquid-liquid microextraction and detected by a gas chromatograph-mass spectrophotometer. The results showed relatively high mean concentrations of organophosphate pesticides ranging from 0.87 to 3.229 μg/L in the river water and low concentrations of organochlorine pesticides, except for 1,3-dichloropropene with the concentration of 3.58 μg/L. Alachlor had a rather high concentration (2.44 μg/L) in the river water. The concentration of pesticides in the drinking water had been reduced to an acceptable amount. The major part of pesticides removal occurred in coagulation-flocculation and rapid sand filtration units (87 %) due to the hydrophobic nature of pesticides and the use of GAC in the filtration unit. Based on the risk assessment estimates, the total hazard quotient (THQ) for all the pesticides was much less than one. The value of THQ was higher in younger individuals and children for all the given pesticides. The highest value of THQ in children was 0.2 which was attributed to aldrin. Similarly, the carcinogenic risk (CR) of aldrin for children and teenagers was in the unsafe range (more than 10^-4) while the CR for other target compounds in all the age groups was negligible (10^-4-10^-6 or less). The high concentration of pesticides in the river water might be concerning and therefore selling and using pesticides, especially the banned ones, should be more regulated.

Concentrations and health risks of heavy metals in five major marketed marine bivalves from three coastal cities in Guangxi, China

Seafood consumption provides essential elements to humans while also posing risks to human health. A total of 2610 individuals of five edible marine bivalve species (Ruditapes philippinarum, Paphia undulata, Meretrix meretrix, Sinonovacula constricta and Meretrix lyrata) were randomly sampled from six farmer markets in three cities (Beihai, Qinzhou and Fangchenggang) in the southernmost coastal region of China. The concentrations of heavy metals (Cu, Pb, Zn, Cd, Cr, Hg and As) were determined by inductively coupled plasma mass spectrometry (ICP-MS). The estimated daily intake (EDI), target hazard quotient (THQ), total hazard index (HI), and target cancer risk (TR) were calculated to evaluate potential human health risks from bivalve consumption. The mean concentrations of metals in the tissues of bivalves descended in the order Zn > Cu > As > Cd > Cr >Pb > Hg in descending order, and the concentrations varied substantially among the five bivalves. Heavy metal concentrations in edible tissues of most bivalve samples were below the safety limits set by national and international regulations, and there were significant correlations between certain metal concentrations. The EDI values for each metal in each bivalve were significantly lower than the corresponding PTDI (provisional tolerable daily intake) values. Health risk assessment showed that although there is no noncarcinogenic health risk for local residents exposed to individual or combined metals from these bivalves, there is a carcinogenic risk from Cd and Cr exposure. Thus, in the long term, monitoring and controlling bivalve consumption will be important. Although current accumulation levels of bivalves are safe, continued and excessive lifetime consumption over 70 years may pose a target cancer risk.

Assessment of organochlorine pesticides and health risk in tobacco farming associated with River Barandu of Pakistan

Diffuse pesticide pollution through tobacco fields is a serious threat to both natural integrities and living beings because tobacco is known as a pesticide-intensive crop. Upsurge in the knowledge of detrimental impacts caused by organochlorine pesticides (OCPs) has made them a burning issue particularly in developing countries. Pakistan is a country famous for its agro-based economy and simultaneously is the second most significant pesticide consumer in South Asian countries. The studied area is tobacco hub of the country. Thus, the present work is aimed to investigate the contamination profile that highlights the ecological and health risk posed by OCPs in River Barandu, located in the proximity of tobacco farming region. ΣOCP levels in sediments ranged between 32.918 and 98.810 ng/g and in water between 0.340 and 0.935 μg/L. Hexachlorocyclohexanes (HCHs) and heptachlor were the most prevailing pesticides in both matrices of the river. Isomeric composition of DDTs and HCHs highlighted that the β-HCH and p,p'-DDT were dominant isomers in water, while α-HCH and p,p'-DDT in sediment compartment. Enantiomeric compositions of HCH and DDT indicate both recent and historic uses of these compounds in the area. Indirect contamination through nearby tobacco clusters has been depicted through spatial analysis. Ecological risk assessment based upon the risk quotient (RQ) method revealed that α-endosulfan, dieldrin, heptachlor, and ∑HCHs represent a very high level of ecological risks. The OCPs' lifetime carcinogenic and non-carcinogenic health risks associated with dermal exposure to river's water were considered nominal for surrounding populations. However, detailed ecological and health risk studies are recommended considering the bio-accumulating nature of these contaminants in the food chain.

Identification and regulation of ecotoxicity of polychlorinated naphthalenes to aquatic food Chain (green algae-Daphnia magna-fish)

Polychlorinated naphthalenes (PCNs) are widely distributed in the aquatic environment and can be transmitted through the food chain, which can amplify their toxic effects on human. To inhibit their transmission in the trophic level, this study aimed to predict the joint toxicity mechanism of polychlorinated naphthalenes (PCNs) to the key organisms and control scheme of its toxicity in the aquatic food chain (green algae-Daphnia magna-fish). The toxic effect grade and mode of action (MoA) of PCNs on the food chain were first predicted to guide the establishment of toxic mechanism model. QSAR models were constructed to quantify the mechanism of aquatic toxicity due to PCNs. The results showed the PCN compounds studied were highly toxic at all the trophic levels of the aquatic food chain. The binding ability of PCNs to the aquatic organisms was the main factor causing the toxicity of PCNs in the food chain, followed by electronic parameters E_HOMO and E_LUMO. Moreover, the binding ability between PCNs and food chain receptors was related to the molecular hydrophobicity, the hydrophobicity can be changed by adjusting the ability of PCNs to be adsorbed by sediment and their chlorine substituents, while the effect of PCNs electronic parameters (E_HOMO and E_LUMO) can be adjusted by their solvation effect. In addition, the macro-control scheme of PCN-based aquatic toxicity mechanism was established, and the molecular dynamics (MD) simulation confirmed its effectiveness and accessibility. The MD simulation showed the inhibition effect of nutrition-grade toxicity in the food chain was significant when the external stimulation conditions of solvation, anaerobic dechlorination and molecular adsorption were improved, with the decrease range of 66.26-263.16%, 198.93-323.98% and 189.24-549.48%, respectively. This work reveals new insights into the mechanism of PCNs joint toxicity to aquatic ecosystem food chain and develop appropriate strategies for its ecological risk management.

Pesticides contamination in the Thamirabarani, a perennial river in peninsular India: The first report on ecotoxicological and human health risk assessment

This study evaluates the distribution of pesticides and assesses the ecological and human health risks associated with pesticide residues concentration in the Thamirabarani River, the only perennial river in Tamil Nadu, India. Observed a variation in the pesticide concentration in the water (not detected (ND)-31.69 μg/L), sediments (ND-14.77 μg/kg), and fish (0.02-26.05 μg/kg). Endosulfan, aldrin, and endrin were the predominant organochlorine pesticides present in water, sediments, and fish. The average concentration of pesticides (except endosulfan) in water and sediments was found to be below the acceptable threshold as per the water and sediment quality guidelines, posing no ecological hazard to aquatic organisms. The calculated risk quotient and toxic unit (0.1 > TU/RQ ≤ 1) represent low-to-medium acute and chronic toxicity to the aquatic organisms inhabiting the river basin. The average concentration of pesticides in fish (Labeorohita) was also below the maximum residual limits set by the Codex Alimentarius Commission (CAC). However, the calculated daily intakes of endosulfan, aldrin, and endrin were above the CAC-acceptable daily intake guidelines. The human health risk assessment showed that children and adults exposed to pesticides in water and sediments through ingestion and dermal contact could have higher cancer risks (CR > 10^-4) than inhalation. This study recommends implementing effective and routine pollution management schemes to avoid pesticide threats to aquatic and human health.

Endocrine-disrupting organochlorine xenobiotics in fish products imported from Asia-an assessment of human health risk

The sources of endocrine-disrupting persistent organochlorine compounds (OC) are environmental pollutants. Contaminated food is a direct result of environmental pollution, and fish are considered as the main source of OC in the human diet. This study aimed to analyze the contamination of imported fish fillets with organochlorine pesticides (OCPs) and polychlorinated biphenyl (PCB) congeners in the context of potential health risks of consumers in Poland in the light of the new tolerable weekly intake (TWI) values. The tested compounds in fish products were determined by liquid-liquid extraction and gas chromatography mass spectrometry (GS-MS) method. Despite the detection of almost all pesticides analyzed in the fish fillets tested, the risk factor (hazard quotient) was significantly lower than 1.0, ranging from 0.003 to 0.013. Considering the previous recommended TWI value (14 pg-TEQ/kg bw/week), the estimated weekly intake was lower at 43-53% of TWI. However, according to the new TWI values set by the EFSA in 2018, the estimated weekly intake was about three times higher than the TWI. This raises concerns regarding threats to consumer health.

Presence of antibacterial substances, nitrofuran metabolites and other chemicals in farmed pangasius and tilapia in Bangladesh: Probabilistic health risk assessment

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ANCs in pangasius and tilapia, fish feed, pond sediments and water were analysed comprehensively.

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Residual ANCs except heavy metals were not found in farmed pangasius and tilapia flesh.

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Residual toxic heavy metals lead and chromium in fish were above the permissible limit.

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Heavy metals sourced primarily from fish feed with secondary sources such as groundwater.

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Lead and chromium concentrations in fish flesh pose potential carcinogenic risks to human health.

Intensive feeding and the use of drugs and other chemicals for enhancing yield characterised commercial pangasius and tilapia aquaculture in Bangladesh. The residual presence of prohibited antibacterial substances, nitrofuran metabolites and other chemicals (ANCs) in fish, and their effect on public health are a concern for consumers. This study collected samples from 15 pangasius and 15 tilapia ponds to assess the contamination of ANCs, including pesticides, dyes and heavy metals in fish flesh, and heavy metals in feed, sediments and water. Antibacterial substances, nitrofuran metabolites and dyes in fish flesh were detected using LC–MS/MS. Organochlorine pesticides and heavy metals were detected applying GC–MS and AAS, respectively. We found very low residue of the most ANCs in pangasius and tilapia flesh, however, both species contained heavy metals, particularly lead (Pb) and chromium (Cr). The level of metal contamination was affected by the age of the pond; the highest concentration of Pb was in pangasius from old ponds (> 10 years), and the highest concentration of Cr was found in pangasius from new ponds (< 10 years), and tilapia from old ponds. The feed sampled in this study, particularly the commercial pellet and farm-made feed, were highly contaminated with heavy metals. Pond water and sediments were contaminated by heavy metals; fish, water and sediment samples from older ponds had higher concentrations of heavy metals. The concentration of these heavy metals in fish flesh above regulatory limits poses potential risks to human health. To ensure the production of safe fish for human consumption, commercial aquaculture in Bangladesh requires a functional regulatory framework.

A Review of Biological Monitoring of Aquatic Ecosystems Approaches: with Special Reference to Macroinvertebrates and Pesticide Pollution

Biological monitoring is the evaluating changes in the environment using the biological responses with the intent of using such information in quality control of the ecosystem. Biomarkers and bioindicators are two main components of the hierarchy of biomonitoring process. Bioindicators can be used to monitor changes of ecosystems and to distinguish alteration of human impact from natural variability. There is a wide range of aquatic taxa such as macroinvertebrates, fish and periphyton, planktons which are successfully used in the biomonitoring process. Among them, macroinvertebrates are an important group of aquatic organisms that involves transferring energy and material through the trophic levels of the aquatic food chain and their sensitivity to environmental changes differs among the species. The main approaches of assessing freshwater ecosystems health using macroinvertebrates include measurement of diversity indices, biotic indices, multimetric approaches, multivariate approaches, Indices of Biological Integrity (IBI), and trait-based approaches. Among these, biotic indices and multimetric approaches are commonly used to evaluate the pesticide impacts on aquatic systems. Recently developed trait-based approaches such as SPEcies At Risk of pesticides (SPEAR) index was successfully applied in temperate regions to monitor the events of pesticide pollution of aquatic ecosystems but with limited use in tropics. This paper reviews the literature on different approaches of biomonitoring of the aquatic environment giving special reference to macroinvertebrates. It also reviews the literature on how biomonitoring could be used to monitor pesticide pollution of the aquatic environment. Thus the review aims to instil the importance of current approaches of biomonitoring for the conservation and management of aquatic ecosystems especially in the regions of the world where such knowledge has not been integrated in ecosystem conservation approaches.

Determination of toxic heavy metals in fish samples using dispersive micro solid phase extraction combined with inductively coupled plasma optical emission spectroscopy

Monitoring of toxic heavy metals in fish samples is a matter of a great importance from the nutritional and toxicological points of view. A dispersive micro solid phase extraction (dµSPE) for preconcentration of trace Pb, Cd, Hg, Co, Ni ions using pectin coated magnetic graphene oxide (pectin/Fe₃O₄/GO) is presented. Inductively coupled plasma optical emission spectroscopy (ICP/OES) was utilized for analyzing the samples. The influence of parameters name as pH, extraction time, sample volume and amount of sorbent were optimized using central composite design (CCD) methodology. Detection and quantification limits were between 0.01 and 0.21 µg g^-1 and 0.04-0.67 µg g^-1 of fresh fish sample, respectively. Accuracy of the method verified using certified reference materials (NIST-SRM-1946). Concentration of the toxic heavy metals were successfully determined in 11 different fish samples using the proposed method.

Human health risk assessment of heavy metals in aquatic sediments and freshwater fish caught from Thamirabarani River, the Western Ghats of South Tamil Nadu

Industrialization and advancements in agriculture are increasingly the cause of environmental concerns and need to be addressed. This study was carried out at four sampling sites, viz. Manimuthar (site 1), Tirunelveli (site 2), Srivaikuntam (site 3), and Authoor (site 4), along the Thamirabarani river. The heavy metal concentration in fish and sediments were ranged from 0.001 to 9.505 mg kg^-1 and 0.294 to 106.25 mg kg^-1. The lifetime cancer risk (LCR) values for children and adults were found to be above the acceptable threshold value (ATV) and children were found to be more susceptible to health risks. For all sites except site 4, the LCR of toxic metals except Cd were within the ATV (10^-6-10^-4); the value of Cd was above the ATV, and poses a high cancer risk to the downstream inhabitants. This study advises routine heavy metal monitoring on aquatic organisms along these sites to implement regulatory standards.

Heavy metals risk assessment in fish species (Johnius Belangerii (C) and Cynoglossus Arel) in Musa Estuary, Persian Gulf

In this study the possible health effects of consumption of benthopelagic (Johnius Belangerii (C); JB) and demersal (Cynoglossus Arel; CA) fishes were evaluated. These fish species living in the Musa estuary (the biggest estuary in the south of Iran and in the northern coastline of Persian Gulf) are likely to be polluted with Hg, V, Ni and Tl. The food frequency questionnaire (FFQ) was used to estimate fish intakes in the residents of Mahshahr city. Also, heavy metal concentrations were determined in fishes and compared with the maximum permissible levels (MPLs). The bioaccumulation factor (BAF) showed high bioaccumulation ability for Hg and Tl in both fish spices. The ratio of TDI/EDI showed the importance of the health hazard by both fish consumption. Also, Hg and Tl in fishes had a higher calculated target hazard quotient (THQ) than the limits. Regarding with the high possibility of serious health concerns associated with Hg and Tl contamination in the Musa estuary, it is suggested to do appropriate and urgent actions by the governors.

Metal concentrations in fish from nine lakes of Anhui Province and the health risk assessment

In the present study, to comprehensively investigate the metal contamination in the fish of Anhui Province, four fish species, Ctenopharyngodon idella, Cyprinus carpio, Hypophthalmichthys molitrix, and Hypophthalmichthys nobilis, were collected from nine lakes, and the levels of Zn, Pb, Cr, Cu, Ni, As, Hg, and Cd in the fish muscle were determined. The results showed that the highest concentrations of Zn (7.791 mg/kg), Pb (0.522 mg/kg), Cr (0.030 mg/kg), and Cu (0.767 mg/kg) were found in Tiangang Lake, Xifei Lake, Tiangang Lake and Baidang Lake, respectively. However, metals Ni, As, Hg, and Cd were not detected in all fish samples. In the fish species, the metal bioaccumulation ability was decreased with the following order: C. idellus > H. molitrix > H. nobilis > C. carpio. Furthermore, the target hazard quotient (THQ) was used to assess the health risk via fish consumption. The results indicated for co-exposure; C. idellus would pose a health risk to children at high exposure level (95th) as THQ value was higher than 1. It should be pointed out that Pb contributes most to the total THQs (the ratio was 88%); thus, the contamination of Pb should be paid more attention. This field investigation combined with health risk assessment would provide useful information on the heavy metal pollution in Anhui Province.

Impact of reservoir properties on elemental accumulation and histopathology of European perch (Perca fluviatilis)

This study was conducted on individuals of European perch from six reservoirs in Serbia with different properties, used for different purposes, and situated at different altitudes. Samples of muscle, gills, and liver, as well as water samples, were used for analysis of elemental accumulation. Histopathological (HP) analysis of gills and liver, and Fulton's condition factor (CF) were used as biomarkers. Analysis of Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, S, Se, Si, Sr, and Zn was conducted by inductively-coupled plasma optical emission spectrometry (ICP-OES), and accordingly, metal pollution index and bioaccumulation factor (BAF) were calculated. Elemental accumulation varied considerably both among tissues and reservoirs. Reservoirs located on large low-altitude rivers were the most heavily polluted with metals (Međuvršje, on the Zapadna Morava River, and Lake Sava, on the Sava River). Of three tissues analyzed, the gills were most affected by pollution. The levels of Hg in muscle decreased with an increase in reservoir altitude. Specimens sampled from the highest altitude reservoir were the least affected by HP alterations; however, HP differences between the reservoirs were not statistically significant, and the severity of HP changes was generally low. No significant correlations between the elemental accumulation or HP indices with CF were observed.

Reprotoxicity of glyphosate-based formulation in Caenorhabditis elegans is not due to the active ingredient only

Pesticides guarantee us high productivity in agriculture, but the long-term costs have proved too high. Acute and chronic intoxication of humans and animals, contamination of soil, water and food are the consequences of the current demand and sales of these products. In addition, pesticides such as glyphosate are sold in commercial formulations which have inert ingredients, substances with unknown composition and proportion. Facing this scenario, toxicological studies that investigate the interaction between the active principle and the inert ingredients are necessary. The following work proposed comparative toxicology studies between glyphosate and its commercial formulation using the alternative model Caenorhabditis elegans. Worms were exposed to different concentrations of the active ingredient (glyphosate in monoisopropylamine salt) and its commercial formulation. Reproductive capacity was evaluated through brood size, morphological analysis of oocytes and through the MD701 strain (bcIs39), which allows the visualization of germ cells in apoptosis. In addition, the metal composition in the commercial formulation was analyzed by ICP-MS. Only the commercial formulation of glyphosate showed significant negative effects on brood size, body length, oocyte size, and the number of apoptotic cells. Metal analysis showed the presence of Hg, Fe, Mn, Cu, Zn, As, Cd and Pb in the commercial formulation, which did not cause reprotoxicity at the concentrations found. However, metals can bioaccumulate in soil and water and cause environmental impacts. Finally, we demonstrated that the addition of inert ingredients increased the toxic profile of the active ingredient glyphosate in C. elegans, which reinforces the need of components description in the product labels.

Metals in wild fish from Gaotang Lake in the area of coal mining, China: assessment of the risk to human health

Environmental pollution can cause metal accumulation in aquatic organisms, but information on metal bioaccumulation in wild fish from coal mining areas is limited. We investigated tissue-specific metal accumulation in six economically important fish species common to Gaotang Lake, China, located in a coal mining area. We also conducted an assessment of potential risks to human health from consumption of these fish. Mean concentrations of arsenic, cadmium, cobalt, copper, mercury, lead, and antimony in the muscle of six fish species were below the corresponding Chinese maximum allowable concentrations except chromium and generally comparable with levels in fish reported by other studies. Tissue distribution patterns suggested that chromium and mercury were easily transported to the muscle, but concentrations of the other six metals were higher in the liver and gills. The daily intake of each metal was estimated at 0.002-0.220 g/day/kg body weight, and the non-carcinogenic health risks associated with the consumption of the fish from Gaotang Lake were acceptable. The results suggest that metal bioaccumulation in wild fish is not high in this coal mining area.

Effects of earthworms and effective microorganisms on the composting of sewage sludge with cassava dregs in the tropics

The present study revealed the role of earthworm-effective microorganisms (EM) in converting sewage sludge and cassava dregs into a valuable product. Sewage sludge was toxic to earthworm, therefore it was mixed with cassava dregs in 80:20 proportions (dry weight). Treatments included mixed substrate inoculated versus not inoculated with EM and treated with or without earthworms. The pH, total organic carbon, total nitrogen, and C:N ratio decreased from the initial measurements in the range of 17.43-18.46%, 25.48-33.82%, 19.60-25.37%, and 6.68-14.05% respectively; but electrical conductivity and available phosphorus increased in the range of 113.47-158.16% and 42.42-57.58%, respectively. In addition, they interactively increased total phosphorus from 19.84-63.01% and potassium from 16.41-50.78%, and decreased the polycyclic aromatic hydrocarbons content of substrate from 21.17% to 32.14% with an increase in earthworms from 51.71 to 57.69, respectively. Earthworms and EM could be used together as an efficient method for co-composting sewage sludge plus cassava dregs in the tropics. This could be expected to result in stabilization of waste, increase in nutrients, and reduction of pollutant content. Implications: The first reports of interaction of earthworms and effective microorganisms in the treatment of sewage sludge and cassava dregs in the tropics. Co-composting was an efficient technology for treating sewage sludge and cassava dregs at the same time, in the tropics. The survival rate of the earthworms both> 95%, the highest number of cocoons (640.33) and hatchlings (4694.33) both in EW+EM (Earthworms added and EM inoculated) treatment. Earthworms and EM (Only EM inoculated) interactively increased total phosphorus and potassium content, and decreased the PAH content of substrate with increase in earthworms.

Comparative study of polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) in corals, surrounding sediments and surface water at the Dazhou Island, China

This study investigated polycyclic aromatic hydrocarbons (PAHs) content in corals (Acropora sp.), surficial sediments, and surface seawater, and heavy metals (HMs) contents in corals and sediments from Dazhou Island, Hainan, China. Concentrations of PAHs in seawater and sediment seasonally ranged from 191.5 ng L^-1 to 587.7 ng L^-1, and from 37.9 ng g^-1 to 233 ng g^-1, while levels in corals were higher (185.2-545.0 ng g^-1) compared to those found in sediments, demonstrating bioaccumulation of PAHs by corals. A similar seasonally variation of PAHs was observed in water/sediments and corals, and the proportions of low molecular weight PAHs (LPAHs) in seawater and corals were higher. Pyrolytic and petrogenic contaminations were identified to be the main sources of PAHs. Lower HMs concentrations were detected in corals (9.8-39.4 μg g^-1) than in sediments (65.0-83.3 μg g^-1), but HMs bioaccumulation still occurs in corals. Higher concentrations of HMs in sediment and corals were detected in March and December, especially Mn and Zn. Application of an enrichment factor showed that Cu in corals was delivered from non-crustal materials, and anthropogenic inputs were possibly the main sources. According to Biota Sediment Accumulation Factor, corals could strongly bioaccumulate LPAHs and Cd, and PAHs at a higher (p < 0.05) rate than HMs. There was a lack of correlation between the accumulation of PAHs and HMs in corals based on the cluster analysis. Dual hierarchical clustering analysis result revealed that feeding, instead of symbiosis, might be the main process responsible for the bioaccumulation of PAHs and HMs.

Occurrences and patterns of residual organochlorine pesticides (OCPs) in cultured Chinese mitten crab (Eriocheir sinensis) in China: concentrations, sources, and a human health risk assessment

Seventy Chinese mitten crab samples, encompassing a total of 2100 individuals, were collected from the main production areas in China. The objective was to assess the occurrences and patterns of 23 selected organochlorine pesticides (OCPs) in the edible tissues and assess the associated dietary risk. Concentrations of total residual OCPs in the mitten crabs ranged from 0.72 to 51.51 μg kg^-1, which was comparable to other global aquatic species. Dichlorodiphenyl trichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) were the two main contributors of total OCPs, with the detected values ranging from 0.14 to 30.89 μg kg^-1 and 0.23 to 4.04 μg kg^-1, respectively. Source analysis indicated the coexistence of both residual and recent DDT inputs, while there was no indication of HCH usage in the main production area of mitten crab. In terms of dietary risk, at least eight individual mitten crabs per day are permissible for consumption by local residents, indicating low risk from consumption. The results presented herein should guide the production and consumption of mitten crab, as well as promote the sustainable development of aquaculture in China.

Residues of organochlorine pesticides (OCPs) in aquatic environment and risk assessment along Shaying River, China

Organochlorine pesticides (OCPs) are pesticides with global scale ubiquity, persistence and bioaccumulation, which leave long-term residuals in the water body. OCPs' high toxicity poses significant threats to human health and aquatic biodiversity, making assessment of OCPs' impact on aquatic ecology and human health urgently necessary. In this research, the presence of 16 OCPs in surface water and groundwater along Shaying River, China, as well as OCPs concentration correlations, was investigated at 24 selected sampling sites. At the same time, the ecological risk and human carcinogenic risk were also analyzed by risk quotient method and USEPA's Risk Assessment Guidance, respectively. Results showed that the total concentration of OCPs ranged from 21.0 to 61.4 ng L^-1 in groundwater, and 12.3-77.5 ng L^-1 in surface water. Hexachlorocyclohexane (HCHs) and heptachlor were the prominent contaminants in groundwater, which indicated their use in the recent past and confirmed their persistence. The α-HCH/γ-HCH ratios in groundwater confirmed that γ-HCH (lindane) was used as main substitute of technical HCH in the study area. The correlation analysis illustrated that δ-HCH and γ-HCH played a dominant role in HCHs residue. Heptachlor and α-HCH, as well as endosulfan and heptachlor epoxide, had a strongly significant positive correlation, suggesting an associated usage of the two pair OCPs. An extremely high ecological risk for aquatic organism was observed for γ-HCH, heptachlor and dieldrin, while the carcinogenic risks posed by the selected OCPs in surface water and groundwater were all acceptable.

Bioaccumulation and human health risks of OCPs and PCBs in freshwater products of Northeast China

The levels and spatial distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in freshwater products from Northeast China were investigated by gas chromatography coupled to isotope dilution high-resolution mass spectrometry. All samples were on-spot sampled from main production regions of freshwater products in Northeast China, and these samples were used to systematically assess the potential health risks of OCPs and PCBs associated with consumption of these fishery products. Dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexane (HCHs), hexachlorobenzene (HCB) and PCBs were the major pollutants with 100% detection rates, and their levels ranged from 0.086 to 58, 0.038-3.3, 0.093-4.5 and 0.032-1.4 ng g^-1 wet weight, respectively. The estimated dietary intakes of these contaminants were all below their corresponding acceptable daily intakes. Significant regional differences in the levels of OCPs and PCBs (P ≦ 0.001) were found in samples from Liaoning and Inner Mongolia. The results showed that the concentrations of targeted contaminants in aquatic products had species-specific characteristics, and the levels of targeted pollutants in Oncorhynchus mykiss and Eriocheir sienesis were significantly higher than those in other aquatic product species. Advisories on ten species of aquatic products suggested that consumption of Eriocheir sinensis, Oncorhynchus mykiss and Cyprinus carpio at a rate exceeding 15 meals per month would pose a cancer risk. A health risk assessment indicated that exposure to these pollutants through freshwater products consumption would cause a non-ignorable potential carcinogenic risk to humans.

Safety and quality of the green tide algal species Ulva prolifera for option of human consumption: A nutrition and contamination study

This study sampled U. prolifera and surface seawater from the same locations where green tide broke out in the southern Yellow Sea, in both the year 2016 and 2017. The revealed nutritive components of U. prolifera samples characterized U. prolifera as a high-protein, high-Fe, high ratio of unsaturated lipid acids and low-fat seaweed food, with an ideal ratio of essential and nonessential amino acids. The concentrations and health risk assessment of major micropollutants (heavy metals, pesticides and polycyclic aromatic hydrocarbon (PAHs)) in U. prolifera were also analyzed, respectively. The results showed that the Target Hazard Quotient values of five heavy metals (<1.0 × 10^-1) and the total hazard index of 13 pesticides (<1.5 × 10^-8) were lower than the unity, respectively, and the incremental lifetime cancer risk values of PAHs (<7.4 × 10^-7) were lower than the USEPA limit (1.0 × 10^-6). It suggested that consuming U. prolifera is safe as a food-source option, with PAHs causing relatively higher risks. PAHs from the sites closer to the shore were also found more originated from pyrolysis. We further confirmed the PAH congeners were partly in equilibrium between seawater and U. prolifera. It suggested the possibility that the food safety-risk turned to be above the USEPA limit was not high regardless of the sample collecting time. However, the sources of PAHs and their contributions to the accumulation in U. prolifera need further investigation. This study favored that U. prolifera of the green tide from the southern Yellow Sea has a potential for a nutritious-food production.

Tracking pollutants in dietary fish oil: From ocean to table

Dietary fish oil used in aquafeed transfers marine pollutants to farmed fish. However, the entire transfer route of marine pollutants in dietary fish oil from ocean to table fish has not been tracked quantitatively. To track the entire transfer route of marine pollutants from wild fish to farmed fish through dietary fish oil and evaluate the related human health risks, we obtained crude and refined fish oils originating from the same batch of wild ocean anchovy and prepared fish oil-containing purified aquafeeds to feed omnivorous lean Nile tilapia and carnivorous fatty yellow catfish for eight weeks. The potential human health risk of consumption of these fish was evaluated. Marine persistent organic pollutants (POPs) were concentrated in fish oil, but were largely removed by the refining process, particularly dioxins and polychlorinated biphenyls (PCBs). The differences in the POP concentrations between crude and refined fish oils were retained in the fillets of the farmed fish. Fillets fat content and fish growth were positively and negatively correlated to the final POPs deposition in fillets, respectively. The retention rates of marine POPs in the final fillets through fish oil-contained aquafeeds were 1.3%-5.2%, and were correlated with the POPs concentrations in feeds and fillets, feed utilization and carcass ratios. The dietary crude fish oil-contained aquafeeds are a higher hazard ratio to consumers. Prohibiting the use of crude fish oil in aquafeed and improving growth and feed efficiency in farmed fish are promising strategies to reduce health risks originating from marine POPs.

Development, validation and matrix effect of a QuEChERS method for the analysis of organochlorine pesticides in fish tissue

This study aims to develop and validate a method to determine OCPs in fish tissues, minimizing the consumption of sample and reagents, by using a modified QuEChERS along with ultrasound, d-SPE and gas chromatography with an electron capture detector (GC-ECD), refraining the pooling. Different factorial designs were employed to optimize the sample preparation phase. The validation method presented a recovery of around 77.3% and 110.8%, with RSD lower than 13% and the detection limits were between 0.24 and 2.88 μgkg^-1, revealing good sensitiveness and accuracy. The method was satisfactorily applied to the analysis of tissues from different species of fish and OCPs residues were detected. The proposed method was shown effective to determine OCPs low concentrations in fish tissues, using small sample mass (0.5 g), making the sample analyses viable without the need for grouping (pool).

Organochlorine pesticides across the tributaries of River Ravi, Pakistan: Human health risk assessment through dermal exposure, ecological risks, source fingerprints and spatio-temporal distribution

This study monitored the human health risks through dermal exposure, hazardous risks to ecological integrity, contamination levels, spatio-temporal distribution, and congener specific analysis of organochlorine pesticides (OCPs) across River Ravi and its three northern tributaries (Nullah Bein, Nullah Basanter and Nullah Deg). The residual levels of OCPs isomers were screened for water (n=54) and surface sediment (n=54) samples from twenty seven sampling sites in two alternate seasons (pre-monsoon and post-monsoon). The ∑OCPs concentrations ranged from 13.61 to 1992.18ng/g dry weight and 12.89 to 128.16ng/L with predominance of β-endosulfan and p,p'-DDT in sediment and water matrixes, respectively. Distribution pattern revealed significantly higher concentrations in upstream and midstream, suggesting considerable transboundary OCPs pollution. Calculated ratios of α-HCH/γ-HCH, o,p'-DDT/p,p'-DDT, (DDE+DDD)/∑DDTs and cis/trans-chlordane for water and sediments identified the fresh addition of lindane, technical DDTs and chlordane in the study area. Risk quotient (RQ) based ecological risk was found to be >1 at all studied streams during both seasons and elucidates higher risks for endosulfan (α-endosulfan) and endrin. Human health risk assessment indicated absence of hazardous (non-carcinogenic) risk through bathing in studied streams; as the hazard index values ranged from 1.09E-05 to 2.48E-02 (acceptable limit; <1). However, the calculated carcinogenic risk possessed by OCPs through dermal exposure ranged from 1.39E-10 to 1.98E-05 that highlighted the considerable carcinogenic risk associated to aldrin, dieldrin, p,p'-DDT and β-endosulfan at certain studied sites. Therefore, the high levels of ecological risk and carcinogenic human health risk had emphasized an immediate elimination of ongoing OCPs addition in the studied area.

Concentrations and trophic magnification of polychlorinated naphthalenes (PCNs) in marine fish from the Bohai coastal area, China

Polychlorinated naphthalenes (PCNs) have been found widely in the aquatic environment and can be transferred through food chains, which can magnify or dilute their toxic effects on humans. In this study, PCNs were analyzed in samples of 17 species of fish with different dietary habits collected in the Bohai coastal area in China. Dichloronaphthalenes, which have rarely been quantified in previous studies, were determined. The total PCN concentrations were from 7.3 to 214 pg/g wet weight, and the highest concentration was found in ditrema. The trichloronaphthalenes were the most abundant PCNs, followed by the dichloronaphthalenes and pentachloronaphthalenes. The relatively high contributions of the less-chlorinated homologs to the total PCN concentrations indicated that the main PCN sources around the Bohai were industrial thermal process emissions rather than technical PCN formulations. The trophic magnification factors of the PCN homologs were from 3.1 to 9.9, indicating that PCNs were biomagnified by fish. The trophic magnification factor of dichloronaphthalene and trichloronaphthalenes was 5.8 and 6.4, respectively, indicating for the first time that dichloronaphthalene and trichloronaphthalenes can undergo trophic magnification by fish. The two highest trophic magnification factors were for the pentachloronaphthalenes and hexachloronaphthalenes, probably because these PCNs having fewer vicinal carbon atoms without chlorine atoms attached are less easily biotransformed than the other homologs. The dioxin-like toxicities of the PCNs in the samples, expressed as potential toxic equivalences (TEQs), were assessed. The highest total TEQ was 0.0090 pg/g ww, in Pacific herring, and the hexachloronaphthalenes were the dominant contributors to the total TEQs in the fish samples. The PCN TEQs were much lower than the polychlorinated dibenzo-p-dioxin and dibenzofuran and dioxin-like polychlorinated biphenyl TEQs found in fish from the Bohai in previous studies, and made marginal contributions to overall human exposure to dioxin-like TEQs, suggesting that PCNs pose no toxicological concerns.

Persistent organochlorine pesticides in aquatic environments and fishes in Taiwan and their risk assessment

Organochlorine pesticides (OCPs) are ubiquitous contaminants with high bioaccumulation and persistence in the environment; they can have adverse effects in humans and animals. This study examined residual concentrations in water, sediments, and fishes as well as the association between the health risks of OCPs and fish consumption in the Taiwanese population. Various water and sediment samples from Taiwanese aquaculture and fish samples from different sources were collected and analyzed through gas chromatography tandem mass spectrometry to determine the concentrations of 20 OCPs, namely, aldrin; cis-chlordane; trans-chlordane; dieldrin; endrin; alpha-endosulfan; beta-endosulfan; heptachlor; hexachlorobenzene; alpha-hexachlorocyclohexane; beta-hexachlorocyclohexane; lindane; mirex; pentachlorobenzene; o,p'-dichlorodiphenyltrichloroethane (DDT); p,p'-DDT; and DDT metabolites (o,p'-dichlorodiphenyldichloroethane [DDD]; p,p'-DDD; o,p'-dichlorodiphenyldichloroethylene [DDE]; and p,p'-DDE). None of the analyzed samples was positive for OCP contamination, suggesting no new input pollution from the land through washing into Taiwanese aquaculture environments. However, OCP residues were detected in fishes caught along the coast, namely, skipjack tuna and bigeye barracuda, and in imported fishes, such as codfish and salmon. DDT was the predominant pesticide. The contamination pattern of persistent organic pollutants was as follows: dieldrin > cis-chlordane > hexachlorobenzene, with average concentrations ranging from 0.09 to 2.74 ng/g. The risk was assessed in terms of the estimated daily intake (EDI) for potential adverse indices; the EDI of OCP residues was lower than 1% of the acceptable daily intake established by the Food and Agriculture Organization of the United Nations and World Health Organization. The assessed risk was negligible and considered to be at a safe level, suggesting no association between fish consumption and risks to human health in Taiwan. However, a continuous monitoring program for OCP residues in fishes is necessary to further assess the possible effects on human health.