Large quantities of chlordecone-based insecticides were produced and used throughout the world. One of its most important uses was to control the damage caused by Cosmopolites sordidus in banana-growing regions. In the islands of Martinique and Guadeloupe, 18,000 ha of farmland are potentially contaminated. Despite the key role played by soil macrofauna in agroecosystems, there are currently no data on their contamination. The aim of this study was to explore the fate of chlordecone (CLD) and its transfer to different organisms of the soil food web. Seven species of invertebrates representing different taxonomic groups and trophic levels of the soil communities of Martinique were targeted and collected in six experimental banana fields, with a level of contamination within a range of values classically observed. Soil samples and macrofauna from the study sites were analysed for CLD and chlordecol (CLDOH) its main transformation product. The contamination of the soil fauna were related to delta 15N 15 N (trophic level), proportion of soil ingestion (diet) and types of epidermis (mucus or exoskeleton) in order to study the different mechanisms of macrofauna contamination. Presence of CLD and CLDOH could be quantified in all the soil organisms from contaminated fields. Results showed a significant relationship between the CLD contamination of detritivorous and the ash content of their faeces, suggesting that soil ingestion was the main contamination pathway. In contrast, the exoskeleton-bearing diplopod Trigoniulus coralinus and the soft-bodied earthworm Eudrilus eugeniae, both detritivores with a comparable diet, had similar contamination levels, suggesting that the type of tegument has little influence on bioaccumulation. At the scale of the entire trophic network, a significant relationship was uncovered between delta 15N 15 N values and CLD contamination of the fauna, therefore providing some in situ evidence for a bioamplification process along the soil food chain.

In this study, the level of toxic metals and organochlorine pesticides (OCPs) in the simulated leachate of the soil of a cocoa farm and a nearby river was investigated. Potential mutagenic and genotoxic effects of the river and simulated leachate were evaluated using Ames Salmonella fluctuation assay (Salmonella typhimurium strains TA100 and TA98) and SOS chromotest (Escherichia coli PQ37), respectively. The level of copper, cadmium, arsenic, chromium, nickel, lead, and iron in both the simulated leachate and the river sample was higher than the allowable maximum standard. The concentration of total OCPs was 9.62 and 108.89 mu g/L in the river sample and simulated leachate, respectively. The concentrations of total hexachlorocyclohexanes and dichlorodiphenyltrichloroethane were significantly higher than the standards. Dichlorodiphenyltrichloroethane was the main pollutant in the two samples. Data from the Ames Salmonella fluctuation assay indicated that the tested samples were mutagenic. Similarly, the data from the SOS chromotest corroborate the Ames assay's result. In the E. coli PQ37 system, the two samples induced significant SOS response, an indication of genotoxicity. Comparing the two microbial assays, the E. coli PQ37 showed a slightly higher sensitivity than the Ames Salmonella assay for the detection of genotoxins in the present study. The chemical and organic constituents of the samples were believed to induce these reported genetic and mutagenic effects. These results showed the environmental pollution caused by the indiscriminate use of pesticides in cocoa farming and the potential effects the pollutants might have on exposed aquatic organisms and the human populace.

The extensive use of pesticides has led to the contamination of natural resources, sometimes causing significant and irreversible damage to the environment and human health. Even though the use of many pesticides is banned, these compounds are still being found in rivers worldwide. In this review, 205 documents have been selected to provide an overview of pesticide contamination in rivers over the last 10 years (2014-2024). After these documents were examined, information of 47 river systems was organized according to the types of pesticides most frequently detected, including organochloride, organophosphorus, and pyrethroid compounds. A total of 156 compounds were classified, showing that 46% of these rivers contain organochlorine compounds, while 40% exhibit organophosphorus pesticides. Aldrin, hexachlorocyclohexane, and endosulfan were the predominant organochlorine pesticides with concentration values between 0.4 and 37 x 105 ng L-1. Chlorpyrifos, malathion, and diazinon were the main organophosphorus pesticides with concentrations between 1 and 11 x 105 ng L-1. Comparing the pesticide concentrations with standard guidelines, we found that the Ganga River in India (90 ng L-1), the Owan and Okura Rivers in Nigeria (210 and 9 x 103 ng L-1), and the Dong Nai River in Vietnam (68 ng L-1) exceed the permissible levels of aldrin (30 ng L-1).