Biochemical effects induced by the hexachlorocyclohexanes

Research progress on remediation of organochlorine pesticide contamination in soil

Deteriorated soil pollution has grown into a worldwide environmental concern over the years. Organochlorine pesticide (OCP) residues, featured with ubiquity, persistence and refractoriness, are one of the main pollution sources, causing soil degradation, fertility decline and nutritional imbalance, and severely impacting soil ecology. Furthermore, residual OCPs in soil may enter the human body along with food chain accumulation and pose a serious health threat. To date, many remediation technologies including physicochemical and biological ways for organochlorine pollution have been developed at home and abroad, but none of them is a panacea suitable for all occasions. Rational selection and scientific decision-making are grounded in in-depth knowledge of various restoration techniques. However, soil pollution treatment often encounters the interference of multiple factors (climate, soil properties, cost, restoration efficiency, etc.) in complex environments, and there is still a lack of systematic summary and comparative analysis of different soil OCP removal methods. Thus, to better guide the remediation of contaminated soil, this review summarized the most commonly used strategies for OCP removal, evaluated their merits and limitations and discussed the application scenarios of different methods. It will facilitate the development of efficient, inexpensive and environmentally friendly soil remediation strategies for sustainable agricultural and ecological development.

Evaluation of the Effect of Wheat Germ Oil and Olmutinib on the Thioacetamide-Induced Liver and Kidney Toxicity in Mice

Thioacetamide (TAA) intoxication produces a reproducible standard animal model of induced liver and kidney injuries where free radicals are produced by phase I oxidation reactions, which eventually leads to liver and kidney failure. Wheat germ oil (WGO) is a unique food supplement with concentrated nutrient efficiency and has remarkable antioxidant functions. Olmutinib, on the other hand, is a chemotherapy drug considered safe for kidneys and the liver. Therefore, in this study, WGO and olmutinib were investigated for their effect on TAA-induced liver and kidney damage. Inflammatory markers; interleukin-1 beta (IL-1β); IL-6; and the levels of enzymatic markers ALT (Alanine aminotransferase), AST (Aspartate aminotransferase), LDH (Lactate dehydrogenase), and CK (creatinine kinase) in serum for liver and kidney were analyzed and evaluated along with histopathological changes in the tissue. Thirty male mice 4–6 weeks of age were grouped into five groups of six animals: the control group (saline) and the other groups (Groups II to V), which were given thioacetamide for two weeks. In addition, Group II continued with TAA; Group III was given olmutinib (30 mg/kg), Group IV was given the wheat germ oil (WGO) (1400 mg/kg), and Group V was given (olmutinib (30 mg/kg) + WGO (1400 mg/kg)) for five days. The results suggested that olmutinib treatment potentiated TAA-induced liver and kidney injury. At the same time, WGO efficiently alleviated TAA and TAA–olmutinib toxicity in Groups IV and V. The histological studies also showed reduced damage with WGO in the animal model. Hence, it was concluded that WGO could significantly reduce liver and kidney damage caused by TAA and olmutinib in mice.

Differential Bioaccumulation Patterns of α, β-Hexachlorobenzene and Dicofol in Adipose Tissue from the GraMo Cohort (Southern Spain)

To identify bioaccumulation patterns of α-, β- hexachlorocyclohexane (HCH) and dicofol in relation to sociodemographic, dietary, and lifestyle factors, adipose tissue samples of 387 subjects from GraMo cohort in Southern Spain were analyzed. Potential predictors of these organochlorine pesticides (OCP) levels were collected by face-to-face interviews and assessed by multivariable linear and logistic regression. OCPs were detected in 84.2% (β-HCH), 21.7% (α-HCH), and 19.6% (dicofol) of the population. β-HCH levels were positively related to age, body mass index (BMI), mother's occupation in agriculture during pregnancy, living in Poniente and Alpujarras, white fish, milk and water consumption, and negatively related to being male, living near to an agricultural area, working ≥10 years in agriculture, and beer consumption. Detectable α-HCH levels were positively related to age, BMI, milk consumption, mother's occupation in agriculture during pregnancy, and negatively with residence in Poniente and Alpujarras, Granada city, and Granada Metropolitan Area. Residence near to an agricultural area, smoking habit, white fish and water consumption, and living in Poniente and Alpujarras, Granada city and Granada Metropolitan Area were negatively associated with detectable dicofol levels. Our study revealed different bioaccumulation patterns of α, β-HCH and dicofol, probably due to their dissimilar period of use, and emphasize the need for assessing the exposure to frequently overlooked pollutants.

β-Hexachlorocyclohexane Drives Carcinogenesis in the Human Normal Bronchial Epithelium Cell Line BEAS-2B

Organochlorine pesticides constitute the majority of the total environmental pollutants, and a wide range of compounds have been found to be carcinogenic to humans. Among all, growing interest has been focused on β-hexachlorocyclohexane (β-HCH), virtually the most hazardous and, at the same time, the most poorly investigated member of the hexachlorocyclohexane family. Considering the multifaceted biochemical activities of β-HCH, already established in our previous studies, the aim of this work is to assess whether β-HCH could also trigger cellular malignant transformation toward cancer development. For this purpose, experiments were performed on the human normal bronchial epithelium cell line BEAS-2B exposed to 10 µM β-HCH. The obtained results strongly support the carcinogenic potential of β-HCH, which is achieved through both non-genotoxic (activation of oncogenic signaling pathways and proliferative activity) and indirect genotoxic (ROS production and DNA damage) mechanisms that significantly affect cellular macroscopic characteristics and functions such as cell morphology, cell cycle profile, and apoptosis. Taking all these elements into account, the presented study provides important elements to further characterize β-HCH, which appears to be a full-fledged carcinogenic agent.

A biomonitoring study on blood levels of beta-hexachlorocyclohexane among people living close to an industrial area

BACKGROUND

A chemical plant manufacturing pesticides has been operating since the 1950's in the Sacco River Valley (Central Italy). In 2005, high beta-hexachlorocyclohexane (Beta-HCH) concentrations were found in milk of cows raised and fed near the river. We report the results of a biomonitoring study conducted in this region to evaluate the body burden of Beta-HCH and to identify the determinants of the human contamination.

METHODS

We defined four residential areas by their distance from the chemical plant and the river, and selected a stratified random sample of 626 people aged 25-64 years. We evaluated the association, in terms of the geometric mean ratio (GMR), between several potential determinants and Beta-HCH serum concentrations using multivariate linear regression analysis.

RESULTS

Two hundred forty-six serum samples were analysed to assess Beta-HCH levels (mean concentration: 99 ng/g lipid; Standard Deviation: 121; Geometric Mean: 60.6; Geometric Standard Deviation: 2.65). We found a strong association between Beta-HCH and living in the area close to the river (GMR: 2.00; 95%CI: 1.36-2.94). Beta-HCH levels were also associated with age, level of education, use of private wells and consumption of local food.

CONCLUSIONS

The results suggest that people living close to the river may have been contaminated by Beta-HCH, most likely through water from private wells and privately grown food. A programme of epidemiological and clinical surveillance is on-going on this population.