CYP polymorphisms and pathological conditions related to chronic exposure to organochlorine pesticides

Zooplankton-based adverse outcome pathways: A tool for assessing endocrine disrupting compounds in aquatic environments

Endocrine disrupting compounds (EDCs) pose a significant ecological risk, particularly in aquatic ecosystems. EDCs have become a focal point in ecotoxicology, and their identification and regulation have become a priority. Zooplankton have gained global recognition as bioindicators, benefiting from rigorous standardization and regulatory validation processes. This review aims to provide a comprehensive summary of zooplankton-based adverse outcome pathways (AOPs) with a focus on EDCs as toxicants and the utilisation of freshwater zooplankton as bioindicators in ecotoxicological assessments. This review presents case studies in which zooplankton have been used in the development of AOPs, emphasizing the identification of molecular initiating events (MIEs) and key events (KEs) specific to zooplankton exposed to EDCs. Zooplankton-based AOPs may become an important resource for understanding the intricate processes by which EDCs impair the endocrine system. Furthermore, the data sources, experimental approaches, advantages, and challenges associated with zooplankton-based AOPs are discussed. Zooplankton-based AOPs framework can provide vital tools for consolidating toxicological knowledge into a structured toxicity pathway of EDCs, offering a transformative platform for facilitating enhanced risk assessment and chemical regulation.

The role of genetic polymorphisms for inducing genotoxicity in workers occupationally exposed to benzene: a systematic review

Benzene is used worldwide as a major raw material in a number of industrial processes and also a potent airborne pollutant emitted from traffic exhaust fume. The present systematic review aimed to identify potential associations between genetic polymorphisms and occupational benzene-induced genotoxicity. For this purpose, a total of 22 selected studies were carefully analysed. Our results revealed a positive relation between gene polymorphism and genotoxicity in individuals exposed to benzene, since 17 studies (out of 22) observed positive relations between genotoxicity and polymorphisms in xenobiotics metabolizing genes influencing, therefore, individuals' susceptibility to genomic damage induced by benzene. In other words, individuals with some genotypes may show increase or decrease DNA damage and/or higher or lower DNA-repair potential. As for the quality assessment, 17 studies (out of 22) were categorized as Strong or Moderate and, therefore, we consider our findings to be trustworthy. Taken together, such findings are consistent with the notion that benzene induces genotoxicity in mammalian cells being strongly dependent on the genetic polymorphism. Certainly, such findings are important for clarifying the role of biomarkers related to genotoxicity in human biomonitoring studies.

Detection of 11 carbamate pesticide residues in raw and pasteurized camel milk samples using liquid chromatography tandem mass spectrometry: Method development, method validation, and health risk assessment

This study aimed to use ultra-high-performance liquid chromatography coupled to a triple-quadrupole mass spectrometer to detect 11 carbamate pesticide residues in raw and pasteurized camel milk samples collected from the United Arab Emirates. A method was developed and validated by evaluating limits of detection, limits of quantitation, linearity, extraction recovery, repeatability, intermediate precision, and matrix effect. Due to the high protein and fat content in camel milk, a sample preparation step was necessary to avoid potential interference during analysis. For this purpose, 5 different liquid-liquid extraction techniques were evaluated to determine their efficiency in extracting carbamate pesticides from camel milk. The established method demonstrated high accuracy and precision. The matrix effect for all carbamate pesticides was observed to fall within the soft range, indicating its negligible effect. Remarkably, detection limits for all carbamates were as low as 0.01 μg/kg. Additionally, the coefficients of determination were >0.998, demonstrating excellent linearity. A total of 17 camel milk samples were analyzed, and only one sample was found to be free from any carbamate residues. The remaining 16 samples contained at least one carbamate residue, yet all detected concentrations were below the recommended maximum residue limits set by Codex Alimentarius and the European Union pesticide databases. Nonetheless, it is worth noting that the detected levels of ethiofencarb in 3 samples were close to the borderline of the maximum residue limit. To assess the health risk for consumers of camel milk, the hazard index values of carbofuran, carbaryl, and propoxur were calculated. The hazard index values for these 3 carbamate pesticides were all below 1, indicating that camel milk consumers are not at risk from these residues.

Assessment of methomyl-induced adrenal gland disruption in rat fetuses and pups: Potential protective effects of propolis supplementation

The present study aimed to unravel the possible adverse effects of methomyl on the developing adrenal gland of rat fetuses and pups. Additionally, this study explored the potential improving effects of propolis against these possible hazards induced by methomyl exposure. To achieve that, pregnant rats were divided into four groups: control group, received 1 mL distilled water, propolis group, received 1 mL propolis at a dose of 300 mg/kg, methomyl group, received 1 mL methomyl at a dose of 2 mg/kg, and combined group, received 1 mL methomyl followed by 1 mL propolis, an hour later at the same previous doses. The results revealed that methomyl exposure, during pregnancy and lactation, induced many histological and ultrastructural changes, caused DNA damage and downregulated the expression of steroidogenic acute regulatory (StAR) and CYP11B2 genes in the adrenal glands of both rat fetuses and pups. Interestingly, propolis supplementation demonstrated a remarkable ability to mitigate these deleterious effects and restored the histology and ultrastructure architecture of the adrenal glands of both fetuses and pups, as well as decreased DNA damage and upregulated the expression of StAR and CYP11B2 genes in the adrenal gland of rat fetuses and pups. In conclusion, our study highlights the potential hazardous impact of methomyl exposure during pregnancy and lactation on the development of the adrenal gland in rat fetuses and pups, moreover, the study presents a new approach to alleviate these effects through propolis administration which could be used as a dietary supplement to mitigate the adverse effects of methomyl exposure.

The impact of genetic polymorphisms on genotoxicity in workers occupationally exposed to pesticides: a systematic review

In a world with a rising use of pesticides, these chemicals, although designed to effectively control pests, pose potential threats to the environment and non-target organisms, including humans. Thus, this systematic review aims to investigate a possible association between genetic polymorphisms and susceptibility and genotoxicity in individuals occupationally exposed to pesticides. This review was conducted following the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. A total of 14 carefully selected studies were thoroughly analyzed by two reviewers, who assigned scores based on previously set evaluation criteria. This study classified over half of the chosen studies as having moderate or strong quality, observing a correlation between certain genetic polymorphisms involved in xenobiotic metabolism and genotoxicity in workers exposed to pesticides. Results suggest that the genes associated with xenobiotic metabolism play a substantial role in determining individuals' susceptibility to genomic damage due to pesticide exposure, affecting both their peripheral blood and oral mucosa. This implies that individuals with specific genotypes may experience increased or decreased levels of DNA damage when exposed to these chemicals.

Levels, tissue distribution and isomer stereoselectivity of Dechlorane Plus in humans: A critical review

Exposure of human tissues to Dechlorane Plus (DP) has raised public concern because of the multiple health threats it may pose to humans. Therefore, it is important to summarize the main findings of previous studies on DP in human tissues and to provide potential guidance for future studies. In this paper, DP levels in different populations and human tissues worldwide since 2009 were systematically reviewed. DP levels in human tissues of workers in e-waste dismantling sites in Guangdong Province, China (median 190 ng·g-1 lw in serum) and DP manufacturing plants in Jiangsu Province, China (mean 857 ng·g-1 lw in whole-blood) are the highest reported worldwide. DP levels in tissues of the general population in recent studies are close to those of residents near e-waste dismantling sites, which should be of concern. DP levels in different human tissues were found to be positively correlated with a pattern of blood > breast milk > adipose tissue. The distribution of DP in different human tissues is mainly lipid-driven and may also be influenced by the interaction of DP with proteins such as human serum albumin. Most of the past studies determined the isomer stereoselectivity of DP in human tissues only by comparing the composition of DP in commercial DP products and human tissues, which lacks evidence of mechanism. Recently, a significantly different affinity of DP isomers for proteins was found, which seems to confirm the isomer selectivity of DP in human tissues. We simulated the binding of DP to human serum albumin and DP to thyroid hormone receptor β by molecular docking and found differences in the binding behavior of syn-DP and anti-DP to the selected proteins. Molecular docking seems to be a feasible approach for future studies to predict and reveal the mechanisms of DP behavior and health effects in human tissues.

The Role of Endocrine Disrupting Chemicals in Gestation and Pregnancy Outcomes

Endocrine disrupting chemicals (EDCs) are exogenous substances widely disseminated both in the environment and in daily-life products which can interfere with the regulation and function of the endocrine system. These substances have gradually entered the food chain, being frequently found in human blood and urine samples. This becomes a particularly serious issue when they reach vulnerable populations such as pregnant women, whose hormones are more unstable and vulnerable to EDCs. The proper formation and activity of the placenta, and therefore embryonic development, may get seriously affected by the presence of these chemicals, augmenting the risk of several pregnancy complications, including intrauterine growth restriction, preterm birth, preeclampsia, and gestational diabetes mellitus, among others. Additionally, some of them also exert a detrimental impact on fertility, thus hindering the reproductive process from the beginning. In several cases, EDCs even induce cross-generational effects, inherited by future generations through epigenetic mechanisms. These are the reasons why a proper understanding of the reproductive and gestational alterations derived from these substances is needed, along with efforts to establish regulations and preventive measures in order to avoid exposition (especially during this particular stage of life).

Biomonitoring of organochlorine pesticides and cancer survival: a population-based study

Organochlorine pesticides (OCPs) are endocrine-disrupting chemicals (EDCs) that even at very low levels can cause cancer by increasing the activity of tumor cells and suppressing the immune system. There is also little information on OCPs and survival after diagnosis. The aim of this study was to monitor the concentration of OCPs in the blood serum of cancer patients and its relationship with their socio-demographic characteristics and ultimately that impact on survival time and hazard ratio (HR). This cross-sectional study included 89 diagnosed patients with cancer in Isfahan, Iran. 12 types of OCPs were measured in serum by gas chromatography (7GC) with an electron capture detector and equipped with mass spectrometer (MS). Also, participants' questionnaire was completed to collect information. T-test, ANOVA, and Chi-square tests were used to evaluate the association between serum levels of OCPs and quantitative and qualitative information of patients. Survival analysis was also examined based on Kaplan-Meier method, log-rank test, and Cox model. The mean of total OCPs in patients' serum was calculated to be 1.82 ± 1.36 μg/L. Concentration of 2,4' DDE had a significant relationship with body mass index (BMI) (kg/m²) (P < 0.05). In addition, gender revealed a significant correlation in estimating survival time (P < 0.05). Non-exposure to OCPs showed a positive effect on increasing the life expectancy of patients. Lindane and endosulfan increased the risk of death by 16% and 37%, respectively, with insignificant P value (P > 0.05). The findings of the present study showed adverse effects of OCPs on patients' survival time and increased mortality of HR. Moreover, as the first research conducted in the study area, it is suggested management of environmental, individual and social factors that could be influenced the biological accumulation of OCPs in humans and cause health promotion.

Potential Roles of mtDNA Mutations in PCOS-IR: A Review

Polycystic ovary syndrome (PCOS) is the most common heterogeneous endocrine disease that affecting females in reproductive age. Insulin resistance (IR), an important molecular basis for PCOS, accounts for at least 75% of women carrying this syndrome. Although there have been many studies on PCOS-IR, the detailed mechanisms are not fully understood. As essential hub for energy generation, mitochondria are critical to insulin secretion and normal function, whereas mutations in mitochondrial DNA (mtDNA) result in mitochondrial dysfunctions contributing to the pathophysiology of PCOS-IR via the regulation of balance of oxidative stress (OS), energy deficiency, or hormone metabolism. In the current review, we summarize the clinical and molecular features of PCOS-IR and discuss molecular mechanisms related to mtDNA mutations.

Endocrine disrupting chemicals: effects on pituitary, thyroid and adrenal glands

BACKGROUND

In recent years, scientific research has increasingly focused on Endocrine Disrupting Chemicals (EDCs) and demonstrated their relevant role in the functional impairment of endocrine glands. This induced regulatory authorities to ban some of these compounds and to carefully investigate others in order to prevent EDCs-related conditions. As a result, we witnessed a growing awareness and interest on this topic.

AIMS

This paper aims to summarize current evidence regarding the detrimental effects of EDCs on pivotal endocrine glands like pituitary, thyroid and adrenal ones. Particularly, we directed our attention on the known and the hypothesized mechanisms of endocrine dysfunction brought by EDCs. We also gave a glimpse on recent findings from pioneering studies that could in the future shed a light on the pathophysiology of well-known, but poorly understood, endocrine diseases like hormone-producing adenomas.

CONCLUSIONS

Although intriguing, studies on endocrine dysfunctions brought by EDCs are challenging, in particular when investigating long-term effects of EDCs on humans. However, undoubtedly, it represents a new intriguing field of science research.

Bioaccumulation of organochlorine pesticides in Antarctic krill (Euphausia superba): Profile, influencing factors, and mechanisms

Accumulation of organochlorine pesticides (OCPs) in Antarctic krill (Euphausia superba), a keystone species in the Southern Ocean, is potentially harmful to the Antarctic ecosystem and human health. In the current study, we collected E. superba specimens (including muscle and carapace tissues) from Bransfield Strait in northern Antarctic Peninsula and South Georgia to analyze the profile, influencing factors and mechanisms of OCPs bioaccumulation in them. Results indicated that the biological traits (δ¹³C, δ¹⁵N and lipid contents) of krill were significantly affected by habitat. There may exist growth dilution of OCPs in Antarctic krill and no fresh OCPs input in Antarctica, except for endosulfan I. Based on lipid-normalized concentrations, no significant differences were observed between the two regions at most sampling sites. However, OCP levels showed tissue and sex dependence. Boosted regression trees (BRTs) and partial least squares structural equation models (PLS-SEMs) were built to better investigate the main factors affecting the bioaccumulation of OCPs. Lipid content, negatively correlated with OCP levels, was the main factor. In vitro silicon modeling indicated that CYP3A4 metabolism capacity in krill contributed to the OCP residues except for endosulfan I. The results of this study expand current knowledge of OCPs in Antarctic marine biota, as well as their influencing factors and potential mechanisms.

Polycystic Ovary Syndrome: A Comprehensive Review of Pathogenesis, Management, and Drug Repurposing

Polycystic ovary syndrome (PCOS) is an endocrine-gynecology disorder affecting many women of childbearing age. Although a part of the involved mechanism in PCOS occurrence is discovered, the exact etiology and pathophysiology are not comprehensively understood yet. We searched PubMed for PCOS pathogenesis and management in this article and ClinicalTrials.gov for information on repurposed medications. All responsible factors behind PCOS were thoroughly evaluated. Furthermore, the complete information on PCOS commonly prescribed and repurposed medications is summarized through tables. Epigenetics, environmental toxicants, stress, diet as external factors, insulin resistance, hyperandrogenism, inflammation, oxidative stress, and obesity as internal factors were investigated. Lifestyle modifications and complementary and alternative medicines are preferred first-line therapy in many cases. Medications, including 3-hydroxy-3-methyl-3-glutaryl-coenzyme A (HMG-CoA) reductase inhibitors, thiazolidinediones, sodium-glucose cotransporter-2 inhibitors, dipeptidyl peptidase-4 inhibitors, glucose-like peptide-1 receptor agonists, mucolytic agents, and some supplements have supporting data for being repurposed in PCOS. Since there are few completed clinical trials with a low population and mostly without results on PCOS repurposed medications, it would be helpful to do further research and run well-designed clinical trials on this subject. Moreover, understanding more about PCOS would be beneficial to find new medications implying the effect via the novel discovered routes.

Use In Silico and In Vitro Methods to Screen Hepatotoxic Chemicals and CYP450 Enzyme Inhibitors

In silico and in vitro methods have emerged as valuable tools to rapidly screen and prioritize large numbers of chemicals including new drug entities, food ingredients, and environmental compounds for further in vivo analysis. These methods have been frequently used to conduct screening for a wide range of endpoints including physicochemical properties (e.g., logD), human biokinetic parameters (e.g., metabolism), and human organ toxicities (e.g., hepatotoxicity). This chapter describes a tiered approach of incorporating multiple in silico (quantitative structure-activity relationship, QSAR) and in vitro (e.g., human liver cell models, human liver microsomes) methods into the screening of hepatotoxic chemicals and cytochromes P450 enzyme (CYP) inhibitors. Chemicals are prioritized for further studies (e.g., in vivo animal study) based on the in silico and in vitro results, as well as a literature search for their in vivo exposures (e.g., plasma concentration).

Effects of Organochlorine Pesticide Residues in Maternal Body on Infants

There are many organochlorine pollutants in the environment, which can be directly or indirectly exposed to by mothers, and as estrogen endocrine disruptors can cause damage to the lactation capacity of the mammary gland. In addition, because breast milk contains a lot of nutrients, it is the most important food source for new-born babies. If mothers are exposed to organochlorine pesticides (OCPs), the lipophilic organochlorine contaminants can accumulate in breast milk fat and be passed to the infant through breast milk. Therefore, it is necessary to investigate organochlorine contaminants in human milk to estimate the health risks of these contaminants to breastfed infants. In addition, toxic substances in the mother can also be passed to the fetus through the placenta, which is also something we need to pay attention to. This article introduces several types of OCPs, such as dichlorodiphenyltrichloroethane (DDT), methoxychlor (MXC), hexachlorocyclohexane (HCH), endosulfan, chlordane, heptachlorand and hexachlorobenzene (HCB), mainly expounds their effects on women's lactation ability and infant health, and provides reference for maternal and infant health. In addition, some measures and methods for the control of organochlorine pollutants are also described here.

Spermiogenesis toxicity of imidacloprid in rats, possible role of CYP3A4

This study evaluated the adverse effects of low-dose imidacloprid (IMI) on the characteristics of sperm from male Wistar rats. Thirty mature male rats were equally divided into three groups and orally administered vehicle (Control Group), acceptable daily intake (ADI) concentration of IMI (Group 1), and IMI at a dose 10-fold that of the ADI (Group 2) for 90 days. The findings revealed that IMI caused abnormalities in sperm concentrations and morphologies, accompanied by an imbalance of the gonadal hormone testosterone. Histopathological damage and decrease of testosterone levels were observed in testes from rats treated with IMI. However, estradiol and gonadotropin levels were unchanged after IMI treatment. IMI inhibited the activity of cytochrome P450 3A4 (CYP3A4) and left itself existed in the organism of rats. The indicators relating to sperms and CYP3A4 activity were recovered when rats were co-treated with IMI and CYP3A4 inducer rifampicin together. These results indicated that low-dose IMI exposure caused sperm abnormalities through affecting on the spermiogenesis in testis. Inhibition of CYP3A4 activity by IMI largely contributed to its sperm toxicity. Thus, IMI exposure at doses close to real-world settings resulted in sperm toxicity on rats, which might be a potential risk factor for human reproductive diseases.

Adipose Tissue Redox Microenvironment as a Potential Link between Persistent Organic Pollutants and the 16-Year Incidence of Non-hormone-Dependent Cancer

We aimed to assess the relationships among the adipose tissue's (AT) oxidative microenvironment, in situ accumulated persistent organic pollutant (POP) concentrations, and cancer development. POP and oxidative stress levels were quantified in AT samples from 382 adults recruited within the GraMo cohort (2003-2004) in Granada (Spain). The 16-year cancer incidence was ascertained by reviewing health/administrative databases. Cox-regression models and mediation analyses were performed. The enzymes superoxide dismutase (SOD) and glutathione reductase (GRd) were positively associated with the risk of non-hormone-dependent (NHD) cancer [adjusted hazard ratio (HR) 1.76; 95% confidence interval (CI): 1.17, 2.64 and HR 2.35; 95% CI: 1.41, 3.94, respectively]. After adjustment for covariates, polychlorinated biphenyl-138 (PCB-138) (HR 1.78; 95% CI: 1.03, 3.09), β-hexachlorocyclohexane (β-HCH) (HR 1.70; 95% CI: 1.09, 2.64), and hexachlorobenzene (HR 1.54; 95% CI: 1.02, 2.33) were also positively associated with the risk of NHD cancer. Although confidence intervals included the null value, probably because of the modest number of cancer cases, we observed a potential mediation effect of SOD and GRd on the associations between β-HCH and the risk of NHD tumors (percent mediated = 33 and 47%, respectively). Our results highlight the relevance of human AT's oxidative microenvironment as a predictor of future cancer risk as well as its potential mediating role on POP-related carcinogenesis. Given their novelty, these findings should be interpreted with caution and confirmed in future studies.

Role of CXCL12, TP53 and CYP1A1 gene polymorphisms in susceptibility to pediatric acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most common type of childhood leukemia and represents one third of all pediatric malignancies. Epidemiological studies have shown that various genetic factors play a crucial role in leukemogenesis. Recent genetic association studies on cancer risk have focused on the effects of single-nucleotide polymorphisms (SNPs) in genes that regulate inflammation and tumor suppression, such as chemokines, TP53 and cytochrome P450s (CYPs). Genetic polymorphisms in the 3' untranslated region of the C-X-C motif chemokine ligand 12 (CXCL12; rs1801157) and TP53 (rs1042522) genes have been suggested to influence the risk of ALL in children, while other studies have indicated an association between the CYP1 subfamily A member 1 (CYP1A1)*2C (rs1048943) allele and leukemia risk. The aim of the present study was to investigate the possible association of rs1801157 (CXCL12), rs1042522 (TP53) and rs1048943 (CYP1A1*2C) SNPs with an increased susceptibility of developing ALL. These SNPs were analyzed in 86 children or adolescent patients with ALL and 125 control subjects by PCR-restriction fragment length polymorphism and allelic-specific chain reaction techniques. A higher frequency of CYP1A1*2C heterozygotes and TP53 rare homozygotes, which include the proline (Pro)/Pro genotype, was observed among children with ALL and control subjects, whereas no significant differences were observed for the CXCL12 SNP. Furthermore, the analysis of various allelic combinations of the aforementioned gene polymorphisms demonstrated a markedly increased risk of developing ALL in children. In conclusion, the present study demonstrated that there was a strong association between CYP1A1*2C heterozygotes, as well as the TP53 Pro/Pro genotype, and an increased susceptibility for pediatric ALL in Caucasians.

Organohalogens: A persisting burden in Slovenia?

Persistent organic pollutants (POPs) represent a concern for the environment and human health due to their persistence and toxicity. Exposure in Slovenia is geographically differentiated because the country, as part of former Yugoslavia, has a history of industry and regional contamination and is - at the same time - known for its clean nature. The PCB pollution of the Krupa River drew the public's attention to the chemical burden of Slovenians, and the demand for studies has been rising since. We assessed the exposure of men (n = 548) and primiparous women (n = 536) to POPs in 12 regions of Slovenia as well as exposure pathways via questionnaires. Most PCDD/Fs, PCBs, and PBDEs could be determined in pooled samples of maternal milk at low concentrations (1.57 pg/gTEQ, 1.47 pg/gTEQ, and 1076 pg/g fat, respectively), but a much lower number of compounds could be measured above the LOQ in pooled men's plasma samples (PCDD/Fs 0.08 pg/gTEQ, PCBs 0.007 pg/gTEQ, ΣPBDE 920 pg/g), and only HCB, p,p'-DDE, ΣDDT, and the non-dioxin-like PCB congeners 138, 153, and 180 could be determined in individual samples of milk (concentration range 5-60 ng/g fat). In individual samples of men's serum, only p,p'-DDE and ΣPCB were detected at concentrations of 0.25 ng/g and 0.3 ng/g, respectively. Nonetheless, we were able to differentiate between polluted and unpolluted areas on a national level, with higher exposure levels in the PCB polluted region of Bela Krajina, the industrial region Zasavje, and the capital, Ljubljana. Despite low concentrations, determinants of exposure, such as age, proximity to roads, old building materials, private water supplies, and consumption of alcohol, fish, meat, and eggs that have previously been observed only at higher levels could still be identified. Furthermore, levels of PCBs and PBDEs were highly correlated suggesting common exposure sources and pathways, whereas PCDD/Fs were correlated to a lesser extent. The calculated ratio between DDT and DDE in maternal milk samples was decreasing with the year of sampling, suggesting no ongoing exposure to DDT. The study findings suggest low exposure of men and lactating women to legacy pollutants in Slovenia, which gave rise to the hypothesis that Slovenia's geographical location might provide shelter from the long-range transport of POPs via Westerly winds. This hypothesis remains to be confirmed within future studies.

Perspective on prenatal polychlorinated biphenyl exposure and the development of the progeny nervous system (Review)

The developmental origins of health and disease concept illustrates that exposure in early life to various factors may affect the offspring's long-term susceptibility to disease. During development, the nervous system is sensitive and vulnerable to the environmental insults. Polychlorinated biphenyls (PCBs), which are divided into dioxin-like (DL-PCBs) and non-dioxin-like PCBs (NDL-PCBs), are synthetic persistent environmental endocrine-disrupting chemicals. The toxicological mechanisms of DL-PCBs have been associated with the activation of the aryl hydrocarbon receptor and NDL-PCBs have been associated with ryanodine receptor-mediated calcium ion channels, which affect neuronal migration, promote dendritic growth and alter neuronal connectivity. In addition, PCB accumulation in the placenta destroys the fetal placental unit and affects endocrine function, particularly thyroid hormones and the dopaminergic system, leading to neuroendocrine disorders. However, epidemiological investigations have not achieved a consistent result in different study cohorts. The present review summarizes the epidemiological differences and possible mechanisms of the effects of intrauterine PCB exposure on neurological development.

Role of Endocrine-Disrupting Chemicals in the Pathogenesis of Non-Alcoholic Fatty Liver Disease: A Comprehensive Review

Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver disorder, affecting around 25% of the population worldwide. It is a complex disease spectrum, closely linked with other conditions such as obesity, insulin resistance, type 2 diabetes mellitus, and metabolic syndrome, which may increase liver-related mortality. In light of this, numerous efforts have been carried out in recent years in order to clarify its pathogenesis and create new prevention strategies. Currently, the essential role of environmental pollutants in NAFLD development is recognized. Particularly, endocrine-disrupting chemicals (EDCs) have a notable influence. EDCs can be classified as natural (phytoestrogens, genistein, and coumestrol) or synthetic, and the latter ones can be further subdivided into industrial (dioxins, polychlorinated biphenyls, and alkylphenols), agricultural (pesticides, insecticides, herbicides, and fungicides), residential (phthalates, polybrominated biphenyls, and bisphenol A), and pharmaceutical (parabens). Several experimental models have proposed a mechanism involving this group of substances with the disruption of hepatic metabolism, which promotes NAFLD. These include an imbalance between lipid influx/efflux in the liver, mitochondrial dysfunction, liver inflammation, and epigenetic reprogramming. It can be concluded that exposure to EDCs might play a crucial role in NAFLD initiation and evolution. However, further investigations supporting these effects in humans are required.

Evaluation of conventional and non-conventional biomarkers of liver toxicity in greenhouse workers occupationally exposed to pesticides

The liver plays a prominent role in maintenance of homeostasis and is the major organ for xenobiotic metabolism, including pesticides. Conventional liver function tests are widely used to assess hepatocellular and biliary system dysfunction by measuring serum levels of aminotransferases (ALT, AST) and cholestasis enzymes (alkaline phosphatase -ALP- and γ-glutamyl transferase -GGT-), respectively. Although these tests are not entirely specific for liver damage, their specificity increases when measured concurrently, but still have limited usefulness to predict early liver dysfunction. Hence, non-conventional biomarkers may have a better performance for the early detection of biochemical hepatotoxicity with a greater specificity and sensitivity. A cross-sectional study with a follow-up component was conducted on 175 greenhouse workers regularly exposed to pesticides under integrated production system, and 91 controls living in the same geographical area. All individuals were evaluated for conventional (ALT, AST, ALP, GGT) and non-conventional biomarkers of hepatotoxicity (ornithine transcarbamylase (-OTC-), Arginase-1 -ARG1- and glutathione S-transferase alpha -GSTα-) over two periods of the same crop season, one of high pesticide exposure and other of low exposure. A slight increase in AST was observed in greenhouse workers relative to controls, suggestive of subtle hepatocellular toxicity. Although ALP, ARG1 and GST-α levels were decreased in greenhouse workers, this might be related to a potential homeostatic mechanism that regulates their expression. Altogether, these findings do not represent unambiguous evidence of liver dysfunction (e.g., hepatocellular or biliary system impairment) but may be the result of the low-toxicity pesticides used by greenhouse workers.

"Metal elements and pesticides as risk factors for Parkinson's disease - A review"

Essential metals including iron (Fe) and manganese (Mn) with known physiological functions in human body play an important role in cell homeostasis. Excessive exposure to these essential as well as non-essential metals including mercury (Hg) and Aluminum (Al) may contribute to pathological conditions, including PD. Each metal could be toxic through specific pathways. Epidemiological evidences from occupational and ecological studies besides various in vivo and in vitro studies have revealed the possible pathogenic role and neurotoxicity of different metals. Pesticides are substances that aim to mitigate the harm done by pests to plants and crops, and are extensively used to boost agricultural production. This review provides an outline of our current knowledge on the possible association between metals and PD. We have discussed the potential association between these two, furthermore the chemical properties, biological and toxicological aspects as well as possible mechanisms of Fe, Mn, Cu, Zn, Al, Ca, Pb, Hg and Zn in PD pathogenesis. In addition, we review recent evidence on deregulated microRNAs upon pesticide exposure and possible role of deregulated miRNA and pesticides to PD pathogenesis.

Occupational use of agrochemicals results in inhibited cholinesterase activity and altered reproductive hormone levels in male farmers from Buea, Cameroon

The efficiency of agro pesticides and fertilizers in eliminating pests and scaling up crop yield has motivated farmers to increase their use. Unfortunately, health hazards caused on farmers by these agrochemicals are of growing concern, though not well elucidated. In order to evaluate the effects of occupational exposure to agrochemicals on some key parameters of male farmers' health in Buea Subdivision, Cameroon, a total of 101 men, including 62 farmers using the agrochemicals and a reference population of 39 men not involved in occupational utilization of the agrochemicals, were interviewed on use of protective equipment, exposure symptoms and reproductive health status. Thereafter, serum cholinesterase [acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)] activities, total antioxidant capacity and reproductive hormones [follicle-stimulating hormone (FSH), luteinizing hormone and testosterone] were assessed. Results revealed that farmers mainly used insecticides followed by fungicides, herbicides and fertilizers, but with inadequate protective measures. The use of agrochemicals resulted in several exposure symptoms including weakness, itches, burning sensation, headache, sneezing, coughing and vomiting, as well as decrease in serum AChE activity when compared to the reference population. The agrochemicals impacted negatively on the farmers' reproductive health as evidenced by increased FSH levels. Taken altogether, these results suggested that exposure to agrochemicals adversely affects farmers' health. Therefore, there is a need to further sensitize the farmers on the use of protective equipment to mitigate the exposure and resulting health hazards.

Endocrine Disruptors Acting on Estrogen and Androgen Pathways Cause Reproductive Disorders through Multiple Mechanisms: A Review

Increasing contamination of the environment by toxic compounds such as endocrine disrupting chemicals (EDCs) is one of the major causes of reproductive defects in both sexes. Estrogen/androgen pathways are of utmost importance in gonadal development, determination of secondary sex characteristics and gametogenesis. Most of the EDCs mediate their action through respective receptors and/or downstream signaling. The purpose of this review is to highlight the mechanism by which EDCs can trigger antagonistic or agonistic response, acting through estrogen/androgen receptors causing reproductive defects that lead to infertility. In vitro, in vivo and in silico studies focusing on the impact of EDCs on estrogen/androgen pathways and related proteins published in the last decade were considered for the review. PUBMED and PUBCHEM were used for literature search. EDCs can bind to estrogen receptors (ERα and ERβ) and androgen receptors or activate alternative receptors such as G protein-coupled receptors (GPCR), GPR30, estrogen-related receptor (ERRγ) to activate estrogen signaling via downstream kinases. Bisphenol A, dichlorodiphenyltrichloroethane, dichlorodiphenyldichloroethylene, polychlorinated biphenyls and phthalates are major toxicants that interfere with the normal estrogen/androgen pathways leading to infertility in both sexes through many ways, including DNA damage in spermatozoids, altered methylation pattern, histone modifications and miRNA expression.

Multi-biomarker responses to pesticides in an agricultural population from Central Brazil

We evaluated farmworkers exposed to pesticides and individuals with no history of occupational exposure to pesticides. It was performed the comet assay to evaluate DNA damage. The immunophenotyping of TCD4⁺ lymphocyte subpopulations in peripheral blood was performed by flow cytometry. The single nucleotide polymorphisms (SNPs) in PON1, XRCC1, IL6, IL6R, TNF-α, and MIR137 genes were evaluated by real-time PCR. The exposed group was composed mostly by males (69.44%), with direct exposure to pesticides (56%) and with an average age range of 46 ± 13.89 years, being that 58.3% of farmworkers directly exposed to pesticides and reported the full use of personal protective equipment (PPE). DNA damage was greater in the exposed group (p < 0.05), reinforced by the use of PPE to denote a lower degree of DNA damage (p = 0.002). In this context, in the exposed group, we demonstrated that the use of PPE, age, gender and intoxication events were the variables that most contributed to increase DNA damage (p < 0.0001). Besides, the exposed group showed a significant increase in the subpopulations of T lymphocytes CD3⁺CD4⁺ (p < 0.05) and CD3⁺CD4⁺CD25⁺ (p < 0.0001) and a significant decrease in CD3⁺CD4⁺CD25^-FOXP3⁺ (p < 0.05). SNPs in the TNF-α (rs361525) gene presented a difference in the genotype distribution between the groups (p = 0.002). The genotype distribution of TNF-α (rs361525) was also positively correlated with the DNA damage of the exposed group (r = 0.19; p = 0.01), demonstrating a higher risk of DNA damage in the farmworkers presenting the A mutated allele. Our findings demonstrate that pesticides can exert various deleterious effects on human health by damaging the DNA as well as by influencing the immune system in the case of both direct or indirect exposure and these issues are associated to age, gender, intoxication and the nonuse of PPE.

Immunotoxic role of organophosphates: An unseen risk escalating SARS-CoV-2 pathogenicity

Consistent gathering of immunotoxic substances on earth is a serious global issue affecting people under pathogenic stress. Organophosphates are among such hazardous compounds that are ubiquitous in nature. They fuel oxidative stress to impair antiviral immune response in living entities. Aside, organophosphates promote cytokine burst and pyroptosis in broncho-alveolar chambers leading to severe respiratory ailments. At present, we witness COVID-19 outbreak caused by SARS-CoV-2. Infection triggers cytokine storm coupled with inflammatory manifestations and pulmonary disorders in patients. Since organophosphate-exposure promotes necroinflammation and respiratory troubles hence during current pandemic situation, additional exposure to such chemicals can exacerbate inflammatory outcome and pulmonary maladies in patients, or pre-exposure to organophosphates might turn-out to be a risk factor for compromised immunity. Fortunately, antioxidants alleviate organophosphate-induced immunosuppression and hence under co-exposure circumstances, dietary intake of antioxidants would be beneficial to boost immunity against SARS-CoV-2 infection.

ADORA2A rs5760423 and CYP1A2 rs762551 Polymorphisms as Risk Factors for Parkinson's Disease

Background: Parkinson’s disease (PD) is the second commonest neurodegenerative disease. The genetic basis of PD is indisputable. Both ADORA2A rs5760423 and CYP1A2 rs762551 have been linked to PD, to some extent, but the exact role of those polymorphisms in PD remains controversial. Objective: We assessed the role of ADORA2A rs5760423 and CYP1A2 rs762551 on PD risk. Methods: We genotyped 358 patients with PD and 358 healthy controls for ADORA2A rs5760423 and CYP1A2 rs762551. We also merged and meta-analyzed our data with data from previous studies, regarding these two polymorphisms and PD. Results: No significant association with PD was revealed (p > 0.05), for either ADORA2A rs5760423 or CYP1A2 rs762551, in any of the examined genetic model of inheritance. In addition, results from meta-analyses yield negative results. Conclusions: Based on our analyses, it appears rather unlikely that ADORA2A rs5760423 or CYP1A2 rs762551 is among the major risk factors for PD, at least in Greek patients with PD.

Anthraquinones inhibit cytochromes P450 enzyme activity in silico and in vitro

Anthraquinones exhibit various pharmacological activities (e.g., antioxidant and laxative) and are commonly found in consumer products including foods, dietary supplements, drugs, and traditional medicines. Despite their widespread use, there are limited data available on their toxicokinetic properties. Cytochrome P450 enzymes (CYPs) in the liver play major roles in metabolizing exogenous chemicals (e.g., pharmaceuticals, food ingredients, and environmental pollutants) and endogenous biomolecules (e.g., steroid hormones and cholesterol). Inhibition of CYP activities may lead to serious interactions among these compounds. Here, in silico (quantitative structure-activity relationship modeling) and in vitro (human recombinant enzymes and liver microsomes) methods were used to identify inhibitors of five major CYP isoforms (CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4) among 22 anthraquinones. First, in silico prediction and in vitro human recombinant enzyme assays were conducted for all compounds, and results showed that most of the anthraquinones were potent CYP1A2 inhibitors. Second, five selected anthraquinones (emodin, aloe-emodin, rhein, purpurin, and rubiadin) were further evaluated in human liver microsomes. Finally, plasma concentrations of the five anthraquinones in animal and humans were identified in the literature and compared to their in vitro inhibition potency (IC₅₀ values) towards CYP activities. Emodin, rhein, and aloe-emodin inhibited activities of multiple CYPs in human liver microsomes and potential in vivo inhibition may occur due to their high plasma concentrations. These in silico and in vitro results enabled rapid identification of potential CYP inhibitors and prioritized future in-depth studies.

Parkinson's disease and pesticides: Are microRNAs the missing link?

Parkinson's disease (PD) is a common neurodegenerative disorder that leads to significant morbidity and decline in the quality of life. It develops due to loss of dopaminergic neurons in the substantia nigra pars compacta, and among its pathogenic factors oxidative stress plays a critical role in disease progression. Pesticides are a broad class of chemicals widely used in agriculture and households for the protection of crops from insects and fungi. Several of them have been incriminated as risk factors for PD, but the underlying mechanisms have yet to be fully understood. MicroRNAs (miRNAs) are small, non-coding RNA molecules that play an important role in regulating mRNA translation and protein synthesis. miRNA levels have been shown to be affected in several diseases as well. Since the studies on the association between pesticides and PD have yet to reach definitive conclusions, here we review recent evidence on deregulated microRNAs upon pesticide exposure, and attempt to find an overlap between miRNAs deregulated in PD and pesticides, as a missing link between the two, and enhance future research in this direction.

Heavy metal and pesticide levels in dairy products: Evaluation of human health risk

Cattle milk's health benefits can be compromised by the presence of contaminants. The levels of cadmium, copper, lead and zinc, and residues of dichlorodiphenyldichloroethylene (DDE), dichlorodiphenyldichloroethane (DDD), dichlorodiphenyltrichloroethane (DDT) were determined in soil, milk and cheese samples collected from cow farms from 3 Romanian areas with industrial and agriculture tradition. A new methodology was applied for the determination of the corrected estimated daily intake (cEDI) corresponding to the aggregate dietary exposure. For the risk assessment, we calculated the source hazard quotient (HQs) for each contaminant and the adversity specific hazard index (HIA). Cadmium, copper, lead and zinc, and the sum of DDT levels in soil samples were below maximum residue levels (MRLs). The MRLs of lead and DDD were exceeded in milk and cheese samples from all the 3 areas. The MRLs of copper and zinc were exceeded in cheese samples from area 2 and 3. HQs >10 for lead indicates increased risk, while HQ > 1 for copper and sum of DDT indicates moderate risk for both milk and cheese. By calculating the HI_A, we identified a moderate and increase risk for nephrotoxicity, hepatotoxicity, hematotoxicity, cardiotoxicity and reproduction toxicity after consumption of the dairy products from the 3 areas.

Behavioral impacts of a mixture of six pesticides on rats

Pesticides can potentially contribute to the development of numerous neurodegenerative diseases. This study evaluates the effects of a six-pesticide mixture at doses around the no-observed-adverse-effectlevels (0 × NOAEL, control) and 0.25, 1 and 5 × NOAEL on behavior of Wistar rats. After 3, 6 and 12 months, rats were observed for neurobehavioral changes using the techniques of elevated plus maze and universal problemchamber, and the experiment was conducted thrice. The 3-month exposure revealed a decrease in the cognitive ability at the dose of 5 × NOAEL, and a dose-dependent research activity and anxiety. The 6-month exposurerevealed non-monotonic effects on the cognitive ability, with a decrease by 0.25 and 5 × NOAEL, as well as non-monotonic effects on anxiety, withan increase by 0.25 and 1 × NOAEL. A decrease was also observed in research activity at 5 × NOAEL. However, the 12-month exposure resulted to an increase in cognitive ability by 0.25 × NOAEL and in anxiety by 1 × NOAEL, as well as to a dose-dependent research activity. Repeating the trial showed that the cognitive ability increased from one trial to another, while the researching activity decreased and the anxiety increased by 0× NOAEL. In the groups exposed to pesticides mixture, the trends were different, showing that the exposure to pesticides combined with repeated trials, also influence the response of the animals. The resultsdemonstrate the occurrence of several dose-dependent behavioral responses, with negative effects occurring at doses that are considered safe. This study provides novel insights about time-dependent mixtures biology, and an important perspective to consider when conducting risk assessments.

Does Green Tea Induce Hormesis?

Green tea, and its principal constituent (-)-epigallocatechin-3-gallate (EGCG), are commonly shown to induce biphasic concentration/dose responses in a broad range of cell types, including non-tumor cells, and tumor cell lines. The most active area of research dealt with an assessment of neural cells with application to neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease cell models, often using preconditioning experimental protocols. The general findings demonstrate EGCG-induced hormetic effects resulting in an enhanced acquired resilience within an adaptive and temporally dependent homeodynamic framework. The biphasic dose responses displayed the typical quantitative features of the hormetic dose response with respect to the amplitude and width of the stimulatory response. These findings provide further evidence for the general occurrence of hormetic dose responses with such responses being independent of the biological model, end point, inducing agent, and mechanism. The biphasic nature of these responses has important implications since it suggests optimal dose ranges for end points of public health and therapeutic applications. These findings indicate the need to assess the entire dose-response continuum in order to better define the nature of the dose response, especially in the low-dose zone where such exposures are common in human populations.

Altered activity of xenobiotic detoxifying enzymes at menopause - A cross-sectional study

Xenobiotic metabolism at menopause is an under-investigated topic, albeit women spend one-third of their life in the postmenopausal period. The present study examined the effect of menopause on the in vivo activities of CYP1A2, CYP2A6, xanthine oxidase (XO) and N-acetyltransferase-2 (NAT2) xenobiotic metabolizing enzymes. Enzyme activity was determined in 152 non-smoking volunteers following oral intake of a single dose of 200 mg caffeine and subsequent determination of caffeine metabolite ratios (CMRs) in a 6-h urine sample as follows: CYP1A2: (AFMU+1U+1X)/17U, CYP2A6: 17U/(17U + 17X), XO: 1U/(1U+1X) and NAT2: AFMU/(AFMU+1U+1X). CMRs among groups were analyzed using one-way ANOVA. Significantly lower CYP1A2 and higher CYP2A6 CMRs were observed in postmenopausal compared to premenopausal women and age-matched men. These changes could be attributed to menopause rather than chronological aging since an age-related effect was not observed in premenopausal women or men of any age group. XO CMRs were higher in postmenopausal women and men>50 compared to premenopausal women and men<50, respectively, suggesting an age-related increase in XO activity. No significant alterations were discerned in NAT2 CMRs, in either slow- or rapid-acetylators, indicating that menopause exerts minimal modulation of xenobiotics metabolized by this enzyme. This study provides evidence that the transition to menopause induces significant alterations in xenobiotic-metabolizing enzymes independent of chronological aging suggesting altered metabolism of pharmaceutical and environmental agents.

Oestrogenic Endocrine Disruptors in the Placenta and the Fetus

Endocrine disrupting chemicals (EDCs) are exogenous substances that interfere with the stability and regulation of the endocrine system of the body or its offspring. These substances are generally stable in chemical properties, not easy to be biodegraded, and can be enriched in organisms. In the past half century, EDCs have gradually entered the food chain, and these substances have been frequently found in maternal blood. Perinatal maternal hormone levels are unstable and vulnerable to EDCs. Some EDCs can affect embryonic development through the blood-fetal barrier and cause damage to the neuroendocrine system, liver function, and genital development. Some also effect cross-generational inheritance through epigenetic mechanisms. This article mainly elaborates the mechanism and detection methods of estrogenic endocrine disruptors, such as bisphenol A (BPA), organochlorine pesticides (OCPs), diethylstilbestrol (DES) and phthalates (PAEs), and their effects on placenta and fetal health in order to raise concerns about the proper use of products containing EDCs during pregnancy and provide a reference for human health.

A mixture of routinely encountered xenobiotics induces both redox adaptations and perturbations in blood and tissues of rats after a long-term low-dose exposure regimen: The time and dose issue

Exposure of humans to xenobiotic mixtures is a continuous state during their everyday routine. However, the majority of toxicological studies assess the in vivo effects of individual substances rather than mixtures. Therefore, our main objective was to evaluate the impact of the 12- and 18-month exposure of rats to a mixture containing 13 pesticides, food, and life-style additives in three dosage levels (i.e. 0.0025 × NOAEL, 0.01 × NOAEL, and 0.05 × NOAEL), on redox biomarkers in blood and tissues. Our results indicate that the exposure to the mixture induces physiological adaptations by enhancing the blood antioxidant mechanism (i.e., increased glutathione, catalase and total antioxidant capacity and decreased protein carbonyls and TBARS) at 12 months of exposure. On the contrary, exposure to the 0.05 × NOAEL dose for 18 months induces significant perturbations in blood and tissue redox profile (i.e., increased carbonyls and TBARS). This study simulates a scenario of real-life risk exposure to mixtures of xenobiotics through a long-term low-dose administration regimen in rats. The results obtained could support, at least in part, the necessity of introducing testing of combined stimuli at reference doses and long term for the evaluation of the risk from exposure to chemicals.

Genotoxic, cytotoxic, and cytopathological effects in rats exposed for 18 months to a mixture of 13 chemicals in doses below NOAEL levels

The present study investigates the genotoxic and cytotoxic effects of long term exposure to low doses of a mixture consisting of methomyl, triadimefon, dimethoate, glyphosate, carbaryl, methyl parathion, aspartame, sodium benzoate, EDTA, ethylparaben, buthylparaben, bisphenol A and acacia gum in rats. Four groups of ten Sprangue Dawley rats (5 males and 5 females per group) were exposed for 18 months to the mixture in doses of 0xNOAEL, 0.0025xNOAEL, 0.01xNOAEL and 0.05xNOAEL (mg/kg bw/day). After 18 months of exposure, the rats were sacrificed and their organs were harvested. Micronuclei frequency was evaluated in bone marrow erythrocytes whereas the organs were cytopathologically examined by the touch preparation technique. The exposure to the mixture caused a genotoxic effect identified only in females. Cytopathological examination showed specific alterations of tissue organization in a tissue-type dependent manner. The observed effects were dose-dependent and correlated to various tissue parameters. Specifically, testes samples revealed degenerative and cellularity disorders, liver hepatocytes exhibited decreased glycogen deposition whereas degenerative changes were present in gastric cells. Lung tissue presented increased inflammatory cells infiltration and alveolar macrophages with enhanced phagocytic activity, whereas brain tissue exhibited changes in glial and astrocyte cells' numbers. In conclusion, exposure to very low doses of the tested mixture for 18 months induces genotoxic effects as well as monotonic cytotoxic effects in a tissue-dependent manner.

Genetic polymorphisms as determinants of pesticide toxicity: Recent advances

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Genetic polymorphisms may influence pesticides-induced oxidative damage.Pesticides modulate immune-system cells functionality, leading to the onset of a dangerous pro-inflammatory microenvironment.

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DNA repair genes, Cytochrome P450 s, PON and GST genes have a key role in the metabolism of xenobiotics.

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Many workers are professionally exposed to pesticides with potential health consequences.

Occupational and environmental exposure to pesticides may induce harmful effects on human health by promoting the development of a wide range of disorders. Some of the most recently hypothesized mechanisms are oxidative stress and epigenetic modifications, however biological effects seem to be modulated mainly by the occurrence of genetic polymorphisms. The susceptibility to exposure can be evaluated by studying the most common polymorphisms of genes involved in the metabolism of organophosphorus compounds (cytochrome P450, glutathione transferase, acetyltransferases or paraoxonase 1). The aim of this article is to review recent literature data concerning the influence of genetic polymorphisms on pesticides-induced oxidative damage.

Comparative study of aflatoxin contamination of winter and summer ginger from the North West Province of South Africa

The presence of mycotoxins in staple food can have adverse effect that result in ill health and associated socio-economic losses. Mycotoxins are naturally occurring toxins produced by certain fungi and can be found in staple food plants such as ginger. Ginger is a renowned medicinal plant that is extensively used for cooking and healing. However, this medicinal plant is with little information about its possible mycotoxins contamination. This study determined the occurrence and prevalence of Aflatoxin B1, B2, G1 and G2 and Ochratoxin A contamination in raw ginger sold around Mahikeng, North West Province, South Africa. Samples were collected purposively from various retailers over winter and summer. The analytical procedure optimized was based on immunoaffinity column cleanup (IAC), followed by High performance liquid chromatography with fluorescence (HPLC-FLC) detection. ELISA was also used for mycotoxin screening. On HPLC, the limits of detection and quantification for the four Aflatoxins were 3.9 × 10-7-1.4 × 10 -3 and 1.3 × 10-6 - 4.7 × 10-3 for samples collected in winter, and 3.7 × 10-7- 1.4 × 10-3, LOQ 1.2 × 10-6 - 4.6 × 10-3 for the summer samples. The average recoveries at three spiking levels ranged from 62 to 91% for the summer samples and 70-93% for those collected in winter. A linearity was observed for the analytes whose correlation coefficients were within the range of 0.9995 and 1.000 for the winter samples and 0.9995 and 1.000 for those collected in summer. The results showed that the contamination levels, especially for samples collected in summer were greater than the legally permissible limits. The t-test analysis shows that the mean and standard deviation of the four types of Aflatoxins considered were higher in summer than in winter. The findings of the study indicated that ginger, as for all agricultural commodities, are prone to mycotoxin contamination.

Adverse and hormetic effects in rats exposed for 12 months to low dose mixture of 13 chemicals: RLRS part III

The aim of the current study was to evaluate the effects of a mixture of thirteen common chemicals on rats, after a one-year exposure to doses around the acceptable daily intake (ADIs), using blood and urinary tests. The influence of low doses of the mixture on weight gain, water consumption, feed consumption and feed efficiency, biochemistry parameters, haematological parameters, blood lymphocytes subsets, serum inflammation profile and urine parameters was evaluated. Our mixture caused a moderate monotonic increase of the males' appetite and a non-monotonic increase of anabolism and a monotonic increase of appetite for the females. Regarding biochemical parameters, the exposure to the test mixture caused non-monotonic increases of AST and ALT, a decrease of PChE in males and plausibly a monotonic biliary obstruction in both sexes. Monocytes significantly increased in low dose groups of both sexes. A significant decrease of all the lymphocytes subclasses and an increased expression of TNF-α protein associated with an increased expression of IFN-γ protein observed in various groups. It became apparent that after twelve months of exposure very low doses of the tested mixture had both non-monotonic and monotonic harmful effects on different levels on rats.

Indicator PCBs in farmed and wild fish in Greece - Risk assessment for the Greek population

Health benefits of fish consumption could be counterbalanced by the intake of contaminants after long term fish consumption, burdened even in trace levels. The presence of the indicator PCBs (NDL-PCBs and PCB 118) in farmed and wild seabream and seabass was evaluated. For the determination of PCB, a GC-MS method was developed and evaluated. The association of PCB accumulation in fish with seasonality, locality, production mode and species was also investigated. A new approach for the risk characterisation after exposure to NDL-PCB through fish consumption in Greece was developed, based on the real exposure and the permitted maximum levels of both aggregated dietary exposure and exposure through fish consumption. PCB levels determined in fish were below established permitted limits (6.24 ng/g 95th percentile), while PCB levels and congener distribution varied significantly between farmed and wild fish (p = 0.001). Seasonality was highlighted as an important factor affecting NDL-PCBs accumulation, with high levels coinciding with the reproduction period of each species. Differences were also depicted for sampling sites, with PCB 118 presenting significantly higher values in open seas while NDL-PCB congeners in closed seas. Risk assessment of NDL-PCB intake through fish consumption corrected for the aggregated exposure revealed no risk for the consumers.