Investigation of the incidence of heavy metals contamination in commonly used fertilizers applied to vegetables, fish ponds, and human health risk assessments

Heavy Metal Concentrations in Water, Sediment, and Fish Species in Chashma Barrage, Indus River: A Comprehensive Health Risk Assessment

The increasing levels of heavy metals in aquatic environments, driven by human activities, pose a critical threat to ecosystems' overall health and sustainability. This study investigates the bioaccumulation of heavy metals (Pb, Cu, Cr, and Cd) in water, sediment, and three fish species (Catla catla, Labeo rohita, Cirrhinus mrigala) of different feeding zones within Chashma Barrage, located in the Mianwali district of Punjab, Pakistan, on the Indus River. A comprehensive analysis, including an assessment of associated human health risks, was conducted. Thirty samples from all three sites for each fish species, with an average body weight of 160 ± 32 g, were collected from Chashma Barrage. Water quality parameters indicated suitability for fish growth and health. Heavy metal concentrations were determined using an atomic absorption spectrometer. Results indicated elevated levels of Cd, Cr, and Cu in sediment and Pb and Cd in water, surpassing WHO standard limits. Among the fish species, bottom feeder (C. mrigala) exhibited significantly (P < 0.05) higher heavy metal levels in its tissues (gills, liver, and muscle) compared to column feeder (L. rohita) and surface feeder (C. catla). Liver tissues across all species showed higher heavy metal bioaccumulation, followed by gills. Principal component analysis (PCA) revealed strong correlations among heavy metals in sediment, gills, muscle, and water in every fish species. However, the vector direction suggests that Cr was not correlated with other heavy metals in the system, indicating a different source. The human health risk analysis revealed lower EDI, THQ, and HI values (< 1) for the fish species, indicating no adverse health effects for the exposed population. The study emphasizes the bioaccumulation differences among fish species, underscoring the higher heavy metal concentrations in bottom feeder fish within Chashma Barrage.

Analysis of Heavy Metal Characteristics and Health Risk Assessment of Dried Fish Marketed in Guangzhou, China

This study investigated heavy metal contamination in dried fish sold in Guangzhou, China, and evaluated the resultant non-carcinogenic and carcinogenic health risks. Dried fish samples were purchased from Baiyun, Tianhe, Panyu, and Yuexiu districts in Guangzhou, where the population is substantial. They were randomly acquired in bustling supermarkets and farmers' markets, targeting the most popular dried fish in these areas. Sixty samples from five dried fish types (Stolephorus chinensis, Thamnaconus modestus, Nemipterus-virgatus, river fish, Ctenopharyngodon idella) were analyzed for chromium (Cr), arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg) content. Quantification of the heavy metals were carried out by inductively coupled plasma mass spectrometry (ICP-MS) for Cr, As, Cd, and Pb, and an automatic mercury analyzer for Hg. The median concentration of these heavy metals in dried fish were 0.358 mg/kg, 2.653 mg/kg, 0.032 mg/kg, 0.083 mg/kg, and 0.042 mg/kg, respectively. Pollution severity was ranked as dried Nemipterus-virgatus > dried Stolephorus chinensis > dried Thamnaconus modestus > dried river fish > dried Ctenopharyngodon idella, with As being the most predominant pollutant. All fish types showed severe As pollution. Non-carcinogenic risks were identified in the consumption of dried Nemipterus-virgatus and dried Stolephorus chinensis for both genders, while potential carcinogenic risks were associated with four of the fish types. Women faced higher health risks than men from dried fish consumption. Consequently, we advise consumers to minimize their intake of dried fish and regulatory agencies conduct regular monitoring of heavy metal levels in commercially available dried fish to avert potential health risks.

Implications of Heavy Metal Accumulation in Fish Feed, Water, Sediment, and Different Fish Species in a Polyculture System

Heavy metal bioaccumulation in organisms is primarily a result of dietary uptake. The current study examines the concentrations of heavy metals (Pb, Cd, Cr, and Cu) in fish feed, water, sediment, and three fish species (Catla catla, Labeo rohita, and Cyprinus carpio) from different feeding zones in a polyculture pond system. Furthermore, associated human health risks were also evaluated. The fish samples (n = 25 for each species) were collected from 10 different fish ponds in the Kohat district, Pakistan. Heavy metals were determined using an atomic absorption spectrometer. Results revealed higher concentrations of heavy metals in sediment, followed by water. However, the concentration of heavy metals in fish feed was lower than the standard limits. In the case of fish, the bottom feeder (C. carpio) notably exhibited higher (P < 0.05) levels of heavy metals than the column feeder (L. rohita) and surface feeder (C. catla) fish. Moreover, in the liver of all fish species, the bioaccumulation of heavy metals was higher, followed by the gills. Principal component analysis (PCA) demonstrated a strong correlation of heavy metals in C. carpio gills, flesh, feed, and pond water, while the heavy metals in the liver correlated with the detected metals in sediment. The human health risk analysis shows that bottom feeder fish had higher estimated daily intake (EDI), target hazard quotient (THQ), and hazard index (HI) values (> 1). Consequently, the exposed population may experience adverse health effects. The findings of this study suggest that the bottom feeder (C. carpio) bioaccumulates a higher concentration of heavy metals than column (L. rohita) and surface feeder (C. catla) in the polyculture system.

Sublethal Concentrations of Cadmium and Lead: Effects on Hemato-Biochemical Parameters and Tissue Accumulation in Wallagu attu

The exposure of fish to heavy metals can significantly impact physiological processes and potentially lead to adverse health effects. This study assesses the effects of exposure to Cd and Pb sublethal concentrations in water on Wallagu attu. A total of 48 fish with an average body weight of 145.5 ± 26 g were distributed among three groups (control, Cd-treated, and Pb-treated) within 60 L fiberglass tanks. They were exposed to 30% sublethal concentrations of Cd and Pb for durations of 1, 15, and 30 days. Following this exposure, an assessment was conducted on metal bioaccumulation and hemato-biochemical responses. Results revealed a significantly (P < 0.05) higher concentration of heavy metals in the fish tissues of metals exposed groups than in the control. The concentration of Cd and Pb increases in fish tissues (kidney > gills > intestine) with exposure time. In most cases, the Pb-exposed group exhibited significantly (P < 0.05) higher concentrations of Pb in different tissues than the Cd-treated group. With extended exposure time, the activities of CAT and SOD show a significant decrease in both Cd and Pb-treated groups. However, the reduction in activities was more pronounced in the Cd-exposed group. On 15 and 30 days, the levels of red blood cells (RBC), hemoglobin (HB), hematocrit (HCT), and total protein (TP) decrease in groups exposed to Cd and Pb. The cortisol and glucose levels exhibit a more noticeable (P < 0.05) increase with prolonged exposure to Cd and Pb than the control group. On day 30, the survival rate decreased more in the Pb-exposed group. The findings of this study indicate that exposure to sublethal doses of Cd and Pb induces stress in Wallagu attu, resulting in rapid changes in specific hemato-biochemical parameters.

Evaluation of lead exposure effects on tissue accumulation, behavior, morphological and hemato-biochemical changes in common carp, Cyprinus carpio

BACKGROUND

Heavy metal pollution, particularly lead (Pb), poses a significant threat to aquatic ecosystems and their inhabitants, threatening their delicate balance and long-term viability. This study highlights the urgent need to mitigate heavy metal pollution in aquatic ecosystems.

OBJECTIVE

This study investigates Pb(NO3)2 exposure effects on tissue accumulation, behavioral abnormalities, and hemato-biochemical parameters in common carp (Cyprinus carpio), a widely distributed freshwater fish species.

METHODOLOGY

Fish (115 ± 5.23 g) were exposed to various Pb(NO3)2 concentrations for 10 and 20 days, representing control (0 %), 25 %, 50 %, and 75 % of the LC50 equivalent to 19.33, 38.66, and 58.0 mg/l, respectively. The standard manual procedure was used for blood sampling. The lead concentration in fish tissue was determined using an atomic absorption spectrophotometer.

RESULTS

Results revealed that fish gills showed significant (P < 0.05) increase in Pb(NO3)2 after 10 days, further rising after 20 days. Liver concentrations also rose significantly (P < 0.05) with prolonged exposure and increasing Pb levels. Muscle had lower concentrations. Hematological parameters (RBC, WBC, HB, HCT) decreased with higher Pb(NO3)2 levels. Behavioral and morphological changes were significantly more pronounced in the exposure groups when compared to the control group. Hepatic enzyme activities (AST, ALT), glucose, and lipid levels increased, while total protein decreased.

CONCLUSIONS

The study highlights Pb(NO3)2 harmful effects on common carp, impacting tissue accumulation, hematological parameters, and biochemical disruptions. It emphasizes the need to monitor and mitigate heavy metal pollution in aquatic environments to safeguard freshwater organisms and ecosystems, and to further increase our understanding of Pb toxicity in freshwater ecosystems.

Assessing the risk of consuming fish from Kanyakumari (Tamil Nadu), India: An evaluative study on bioaccumulated heavy metals in different fish species using inductively coupled plasma mass spectrometry

Environmental pollutants which are developing an alarming situation in the contemporary world captured attention in the present research. When it comes to food safety and security concerns it becomes an important field to be studied rigorously as food contributes majorly to human and animal health. The pollution of aquatic ecosystems by heavy metals (HMs) ultimately results in adverse effect on the food chain, which is covered in the current study. Fish is considered to be one of the main components of a balanced diet plate due to its high-quality protein, which sets it apart from other dietary sources. On the other hand, it is also susceptible to the absorption and bioaccumulation of HMs at toxic levels. In our study, we have considered three different species (Nemipterus japonicus, Oreochromis mossambicus, and Lates calcarifer) of fish collected from Kanyakumari, Tamil Nadu (India). Three organs namely liver, gill, and muscle were taken into consideration for the HM profiling using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The Arsenic (As), Cadmium (Cd), Chromium (Cr), Mercury (Hg) and Lead (Pb) were found to be in varied concentrations ranging from 0.1 to 1.13, 0.89-1.45, 9.95-30.66, 0.14-1.62, and 24.69-189.5 µg/kg respectively, in the studied organs of fish. Carcinogenic and noncarcinogenic risk assessments were also done indicating a notable level of Pb and Cr in selected fish species. The Hazard Index (HI) for Oreochromis mossambicus was >1 for adults and children, indicating future possibility of probable health hazards on daily consumption of these fish. In Oreochromis mossambicus, the cancer risk (CR) values for Cr and As were significantly high, particularly for children, indicating a possible occurrence of acute health risk as it exceeded the threshold of 1 × 10-3 and suggesting a significant concern. Though consumption of fish on daily basis in such significant quantity is practically impossible both for adult and children, rendering these species safe.

Exploring a low-cost turbidimetric sensor for available potassium determination in soil

Potassium (K) is among the macronutrients required for crop production and it is absorbed through plant roots from the soil solution. Replenishment of soil K is usually done by fertilizer application; therefore, it is crucial to know the amount of this nutrient that's available in the soil. There's very little literature reporting a turbidimetric method for K determination, and even less in soil samples. The objective of this work is to evaluate a portable low-cost system that allows turbidimetric determination to assess the amount of available K in soil. The turbidimetric method consists of K precipitation with sodium tetraphenylborate (NaTPB). The time and Mehlich-1, Mehlich-1 diluted 1 : 1 and water solutions for the extraction procedure were evaluated. The effect of pH, along with NaTPB volume and sensor signal stability, was also evaluated. With the optimized conditions, calibration of the sensor showed a good linearity (r2 = 0.9982), and the limits of detection and quantification were 0.1 and 0.3 mg L-1 of K, respectively. No significant difference (t test with 95% confidence level) is observed between the results obtained with the sensor and the MP-AES and ICP OES determinations using Mehlich-1 solution for K extraction. The results presented here demonstrate that it is possible to use simple equipment to measure available K in soil on the field by using low amounts of reagents, which could make this analysis more accessible.

Assessing Heavy Metal Contamination in Commonly Used Fertilizers for Polyculture Fish Ponds and Its Implications for Human Health: A Comprehensive Investigation

Over-fertilizing fish ponds can cause pollution, introducing heavy metals into the food chain and posing health risks. The present study investigated the incidence of heavy metals (Pb, Cu, Cd, and Cr) in commonly applied fertilizers, including nitrogen, phosphorus and potassium (NPK), triple superphosphate (TSP), and di-ammonium phosphate (DAP), and their association with heavy metals in water, sediment, and cultured fish species (Catla catla, Labeo rohita, and Cyprinus carpio) in polyculture fish ponds. The study was conducted over 4 months, with four groups in triplicates: control (no fertilizer), group 1 (NPK), group 2 (TSP), and group 3 (DAP). Heavy metal analysis was carried out using atomic absorption spectrophotometry before and after fertilizer application. Significantly (p < 0.05) higher levels of heavy metals were observed in water and sediment after applying fertilizers, with the most pronounced results in group 3 (DAP) followed by group 2 (TSP). The concentration of heavy metals was significantly (p < 0.05) higher in group 3 (DAP) fertilizers compared to other groups. Compared to the control, the concentration and bioaccumulation of heavy metals were significantly (p < 0.05) higher in the fertilizer-applied groups, with notably higher levels in group 3 (DAP). Cluster analysis and the correlation matrix did not show any significant association between the heavy metals and the fertilizers, indicating a complex interplay between the biotic and abiotic factors of the system. The health index (HI) value was < 1 in fish muscles of all studied groups, indicating the fish are safe for consumption. The study recommends monitoring and regulating fertilizer use, especially DAP, to prevent heavy metal contamination, and exploring sustainable alternatives to minimize environmental and health risks.

Assessment of pesticide residues: a comprehensive analysis of seasonal trends and health implications

This study assessed the presence of eight pesticide residues in the Indus River, Mianwali, Pakistan, focusing on three sampling sites (S1, S2, and S3) in water, sediment, and the fish species Cyprinus carpio during both dry and wet seasons. Analysis was conducted using gas chromatography with an electron capture detector. Results indicated elevated pesticide concentrations in both seasons, with levels of 0.84 and 0.62 μg/L in water, 12.47 and 9.21 μg/g/dw in sediment, and 17.33 and 12.17 μg/g/ww in fish, with higher concentrations observed during the dry season. Cypermethrin and carbofuran were the primary pesticides detected in water, while endosulfan and cypermethrin were dominant in sediment and fish tissue, often exceeding standard safety thresholds. Principal Component Analysis (PCA) and cluster analysis revealed stronger correlations between sediment and fish muscle, with varying associations among pesticides across seasons. The Hazard Index (HI) surpassed 1 in both seasons, signaling potential health risks to humans. These findings underscore the substantial risk agricultural pesticides pose to the aquatic ecosystem and food chain, highlighting the urgent need for sustainable agricultural practices and stricter regulations to minimize pesticide use and encourage eco-friendly pest management strategies.

Application of soil amendments to reduce the transfer of trace metal elements from contaminated soils of Lubumbashi (Democratic Republic of the Congo) to vegetables

The extraction of copper and cobalt from mines has led to the contamination of agricultural soils by trace metal elements (TMEs) (e.g. Cu: 204 to 1355 mg/kg). The mining industry is one of the sources of metal discharges into the environment, contributing to water, soil, and air contamination and causing metabolic disorders in the inhabitants of the city of Lubumbashi (R.D. Congo). This study assessed the effectiveness of organocalcareous soil improvers applied to TME-contaminated soils to reduce their transfer to plants. Following a factorial design, increasing doses of organic soil improvers (chicken droppings and sawdust) and agricultural lime were applied to the soils of three market gardens (high, medium, and low Cu contamination). The experiment was monitored for 60 days. Soil physicochemical properties (pH, TOC, and total and available copper, cobalt, lead, cadmium, and zinc (mg/kg)) were determined for the three gardens and in the vegetable biomass. The daily consumption index of the vegetables was determined based on total TME content. The results show that organocalcareous soil improvers did not promote plant growth and survival on soils with high and medium levels of copper contamination. However, on soils with low copper content, organocalcareous soil improvers improved germination and plant survival and reduced the transfer of metals from the soil to the plants. The best germination and plant survival rates were obtained with the lightly contaminated market garden. In addition, the organo-limestone amendments applied to the soils slightly increased the soil pH from acidic to slightly acidic, with pH values ranging from (5.43 ± 0.07 to 7.26 ± 0.33). The daily vegetable consumption index obtained for cobalt in the low-contaminated garden ranged from (0.029 to 0.465 mg/60 kg/day), i.e. from 0.5 to 8.45 times higher than the FAO/WHO limit, unlike the other trace metals (Cd, Cu and Pb) for which the daily consumption index found was lower than the FAO/WHO limit. Organocalcareous soil improvers can only be applied to soils with low levels of TME contamination, but for soils with medium to high levels of metal contamination, new soilless production techniques such as hydroponics or bioponics are needed.

Cobalt Uptake by Food Plants and Accumulation in Municipal Solid Waste Materials Compost-amended Soil: Public Health Implications

One of the most pressing environmental issues is how to properly dispose of municipal solid waste (MSW), which represents both a substantial source of concern and a challenge. The current study evaluated cobalt (Co) accumulation in MSW, their uptake by different vegetables grown for two years, and related human health risks. Vegetables were grown in four different groups, such as one control (ground soil), and the remaining treatment groups (T1, T2, and T3) received varying concentrations of MSW. The analysis of Co was done through an atomic absorption spectrophotometer (AAS). Results revealed that the concentration of Co was higher in all the vegetables (n = 15) grown in soil supplemented with 75% MSW during 2nd growing year. Among all vegetables, the highest concentration of Co was observed in Solanum tuberosum at T3 during 2nd growing year. The pollution load index (PLI) value for vegetables during both growing years was more than 1 except in control soil. The findings indicated that the highest enrichment factor (EF) and hazard resilience index (HRI) value of 0.09 was present in S. tuberosum. Health index values for cobalt in the study were below 1. The HRI < 1 indicated that consumers do not face any immediate health risks. The investigation of Co concentrations in blood samples obtained from individuals residing in different areas contributes a human health perspective to the research. The findings indicate that the concentration of Co rises with an increasing proportion of MSW. While the metal levels in MSW-treated soil were not high enough to classify the soil as polluted, the results recommend that recycling MSW can substitute mineral fertilizers. Nevertheless, the presence of cobalt in MSW may directly affect soil fertility and could impact crop production and human health.

Assessment of heavy metal levels in polyculture fish farms and their aquatic ecosystems: an integrative study addressing environmental and human health risks associated with dam water usage

This study examines the levels of heavy metals in polyculture fish (Labeo rohita, Cyprinus carpio, and Catla catla), water, and sediment in Tanda Dam, Kohat, Pakistan, aiming to understand environmental and health risks. Samples of fish, water, and sediment were collected from 3 fish farms, and heavy metal concentrations were measured using a Flame Atomic Absorption Spectrophotometer (AAS). Results reveal that C. catla exhibited significantly higher (p < 0.05) levels of Zn than other fish species. Conversely, C. carpio showed significantly higher (p < 0.05) concentrations of Pb, Cd, Cr, Mn, Cu, As, and Ni than other species. The heavy metal hierarchy in C. carpio was found to be Zn > Cu > Pb > Cr > Cd > Mn > As > Ni. While heavy metal levels in L. rohita and C. catla generally fell within reference ranges, exceptions were noted for Zn, Pb, and Cd. Conversely, in C. carpio, all metals exceeded reference ranges except for Cu and Ni. Principal Component Analysis (PCA) indicated a close relationship between water and sediment. Additionally, cluster analysis suggested that C. catla formed a distinct cluster from L. rohita and C. carpio, implying different responses to the environment. Despite concerns raised by the Geoaccumulation Index (Igeo) and Contamination Factor (CF), particularly for Cd, which exhibited a high CF. Furthermore, Hazard Index (HI) values for all three fish species were below 1, suggesting low health risks. However, elevated Igeo and CF values for Cd suggest significant pollution originating from anthropogenic sources. This study underscores the importance of monitoring heavy metals in water for both environmental preservation and human health protection. Future research efforts should prioritize pollution control measures to ensure ecosystem and public health safety.

Toxic heavy metals in a landfill environment (Vientiane, Laos): Fish species and associated health risk assessment

Leachates from municipal landfills introduce toxic heavy metals into water, causing bioaccumulation. This study assesses metal levels and potential human health risks associated with consuming Anabas testudineus and Channa striata. Inductively coupled plasma mass spectrometry detected Cd, Cu, Cr, Ni, Pb, and Zn in both fish species. Leachate metal concentrations meet international discharge standards, Cd, Cr, and Pb in the fish exceed the international accepted values. Gastrointestinal tract+liver samples show significant variation between species, particularly in Cd and Pb. EDI, THQ/HI, and TR for the both species fall below TDIs, lower than the limit of 1, and within the acceptable range of the US-EPA permissible limit, respectively. Fish consumption appears safe regarding carcinogenic risk, but exceeding metal limits could impact heavy metals accumulation in the local food chain. Raising public awareness is crucial, and governmental agencies and environmental organizations should enhance waste treatment technologies and enact relevant health legislation.

Analyzing the impact of pesticides on the indus river: contamination levels in water, sediment, fish, and associated human health risks

Pesticides are frequently used to protect crop yields and manage malaria vectors; however, their inadvertent transport into aquatic habitats poses a significant concern. Various anthropogenic activities influence the Indus River in Pakistan. This study aimed to assess the presence of eight pesticide residues at three different sites (Kalabagh, Kundian, and Chashma) in water, sediment, and the fish species (Labeo rohita) during both dry and wet seasons to measure the intensity of this pressure. Pesticide analysis was carried out using gas chromatography equipped with an electron capture detector. The results revealed the highest concentrations of pesticides during both dry and wet seasons at all sites, measuring 0.83 and 0.62 μg/l (water), 12.37 and 9.20 μg/g/dw (sediment), and 14.27 and 11.29 μg/g/ww (L. rohita), respectively. Overall, pesticide concentrations were higher in the dry season than in the wet season across all study sites. Based on detection frequency and concentration in both seasons at all sites, dominant pesticides included cypermethrin and carbofuran (in water), as well as endosulfan and cypermethrin (in sediment and fish tissue). Levels of endosulfan and cypermethrin exceeded standard limits. Moreover, principal component analysis (PCA) indicated no correlation among pesticides in fish tissue, sediment, and water. However, pesticides exhibited different behavior in different seasons. Furthermore, endosulfan and triazophos impose great human health risk, as indicated by the THQ value (> 1). The overall HI value was greater for site 1 in the dry season (8.378). The study concluded that the presence of agricultural pesticides in the Indus River poses a risk to aquatic life and has the potential to disrupt the entire food chain. This highlights the importance of sustainable practices for the study area and Pakistan overall agricultural and environmental sustainability. It is further recommended to strengthen regulations for reduced pesticide use and promote eco-friendly pest management.

Evaluation of the toxic metals, proximate composition and length-weight relationships of selected fish species from the Gadananathi River, Southern Tamil Nadu

The present study reveals toxic metals, proximate composition, and growth conditions in seven fish species, aiding their nutritional importance and conditions. The samples of seven different small indigenous fish species, including Xenentodon cancila, Glossogobious giuris, Pseudambassis ranga, Puntius dorsolis, Mystus vittatus, Dawkinsia filamentosa, and Dawkinsia tambraparaniei, were collected in river Gadananathi, Tamilnadu, India. A total 14 fish samples were analyzed for lead, cadmium, and copper using atomic absorption spectrometry. The standard procedures were used to determine the length-weight and proximate composition of the seven fishes. The findings revealed that the seven fish species had variable amounts of metal buildup. Cu levels were highest in D. tambraparniei gills and lowest in M. vittatus gills and livers; nonetheless, substantial amounts of Cu were found in P. dorsalis livers. In the length-weight correlations of the regression parameters of coefficient value r2, the "a" and "b" values revealed a positive allometric growth rate in all fish species except G. giuris and M. vittatus. However, X. cancila had the highest composition in the proximate analysis, while D. tambraparniei and D. filamentosa had the highest protein content mean value at a significant level (P ≤ 0.05). Overall, discrepancies in nutritional content might be related to species, environmental circumstances, fish age and size, and food availability.