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Patrick Queneherve - One of the best experts on this subject based on the ideXlab platform.
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factors influencing the survivorship of the burrowing nematode radopholus similis cobb thorne in two types of soil from banana plantations in martinique
Applied Soil Ecology, 2010Co-Authors: Christian Chabrier, Celine Carles, Philippe Tixier, Pierre Francois Duyck, Patrick QueneherveAbstract:The burrowing nematode, Radopholus similis (Cobb.) Thorne, causes the most damage to bananas. To minimize nematicide applications, cropping systems that use fallow, crop rotation and clean planting material have been developed in the French West Indies. In order to optimize the benefit of the intercropping period, we studied the survivorship of R. similis in different soil types and conditions. We monitored the survivorship of calibrated populations of R. similis in the laboratory on a Nitisol and on an Andosol, two soils derived from volcanic ashes and pumices. We studied water potentials ranging from 0 to � 700 kPa on undisturbed soil and on soil previously frozen to get rid of living nematodes. Mortality of adult R. similis decreased regularly, and was fairly well described by Teissier’s model. In the previously frozen soils, R. similis survived longer in wet soils (half-life of 21–46 days at 0 to � 5 kPa) than in dry soils (half-life of less than 10 days between � 80 and � 250 kPa). In contrast, in undisturbed soils, R. similis survived longer in dry soils: half-lives ranged from 57 days at � 273 kPa to 17 days at water saturation in the Andosol, and 36 days at � 660 kPa to 14 days at water saturation in the Nitisol. These results are consistent with the absence of anhydrobiosis in R. similis, unlike Pratylenchus coffeae. P. coffeae survivorship curves over time do not follow a model derived from exponential decrease like Teissier’s model. These results also show that the recommended one year host-free period required to sanitize soils cannot be shortened without risk, even if flooding the soil could improve it.
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Survival of the burrowing nematode Radopholus similis (Cobb) Thorne without food: Why do males survive so long?
Applied Soil Ecology, 2010Co-Authors: Christian Chabrier, Yves-marie Cabidoche, Pierre Francois Duyck, Phlippe Tixier, Patrick QueneherveAbstract:The burrowing nematode Radopholus similis is the most damaging banana nematode. To minimize nematicide applications, cropping systems based on fallow, crop rotation, and using clean planting material have been developed in the French West Indies. The survivorship of R. similis in water and soil was evaluated to optimize the collapse of its populations during the intercropping period and to better understand the risk of dissemination of nematodes by run-off water. In both Andosols and Nitisols, survivorship was significantly higher for males than for females. After 180 days, 21.7% of males and 9.8% of females were still alive, whereas no juveniles survived after 150 days. Survivorship was much lower in water and soil solution than in soil. The mean half-life of males was 8.8 days and only 6.2 days for females, but the difference between sexes was less after 1 month: 8% of both males and females in the initial population survived after 35 days. These results suggest that resource allocation for males was directed towards reproduction, whereas females expend energy foraging and laying eggs, and are thus disadvantaged in the absence of host plants. The relatively long survivorship of males of R. similis enables them to fecundate females without competing for food after becoming adults.
Christian Chabrier - One of the best experts on this subject based on the ideXlab platform.
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factors influencing the survivorship of the burrowing nematode radopholus similis cobb thorne in two types of soil from banana plantations in martinique
Applied Soil Ecology, 2010Co-Authors: Christian Chabrier, Celine Carles, Philippe Tixier, Pierre Francois Duyck, Patrick QueneherveAbstract:The burrowing nematode, Radopholus similis (Cobb.) Thorne, causes the most damage to bananas. To minimize nematicide applications, cropping systems that use fallow, crop rotation and clean planting material have been developed in the French West Indies. In order to optimize the benefit of the intercropping period, we studied the survivorship of R. similis in different soil types and conditions. We monitored the survivorship of calibrated populations of R. similis in the laboratory on a Nitisol and on an Andosol, two soils derived from volcanic ashes and pumices. We studied water potentials ranging from 0 to � 700 kPa on undisturbed soil and on soil previously frozen to get rid of living nematodes. Mortality of adult R. similis decreased regularly, and was fairly well described by Teissier’s model. In the previously frozen soils, R. similis survived longer in wet soils (half-life of 21–46 days at 0 to � 5 kPa) than in dry soils (half-life of less than 10 days between � 80 and � 250 kPa). In contrast, in undisturbed soils, R. similis survived longer in dry soils: half-lives ranged from 57 days at � 273 kPa to 17 days at water saturation in the Andosol, and 36 days at � 660 kPa to 14 days at water saturation in the Nitisol. These results are consistent with the absence of anhydrobiosis in R. similis, unlike Pratylenchus coffeae. P. coffeae survivorship curves over time do not follow a model derived from exponential decrease like Teissier’s model. These results also show that the recommended one year host-free period required to sanitize soils cannot be shortened without risk, even if flooding the soil could improve it.
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Survival of the burrowing nematode Radopholus similis (Cobb) Thorne without food: Why do males survive so long?
Applied Soil Ecology, 2010Co-Authors: Christian Chabrier, Yves-marie Cabidoche, Pierre Francois Duyck, Phlippe Tixier, Patrick QueneherveAbstract:The burrowing nematode Radopholus similis is the most damaging banana nematode. To minimize nematicide applications, cropping systems based on fallow, crop rotation, and using clean planting material have been developed in the French West Indies. The survivorship of R. similis in water and soil was evaluated to optimize the collapse of its populations during the intercropping period and to better understand the risk of dissemination of nematodes by run-off water. In both Andosols and Nitisols, survivorship was significantly higher for males than for females. After 180 days, 21.7% of males and 9.8% of females were still alive, whereas no juveniles survived after 150 days. Survivorship was much lower in water and soil solution than in soil. The mean half-life of males was 8.8 days and only 6.2 days for females, but the difference between sexes was less after 1 month: 8% of both males and females in the initial population survived after 35 days. These results suggest that resource allocation for males was directed towards reproduction, whereas females expend energy foraging and laying eggs, and are thus disadvantaged in the absence of host plants. The relatively long survivorship of males of R. similis enables them to fecundate females without competing for food after becoming adults.
Pierre Francois Duyck - One of the best experts on this subject based on the ideXlab platform.
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factors influencing the survivorship of the burrowing nematode radopholus similis cobb thorne in two types of soil from banana plantations in martinique
Applied Soil Ecology, 2010Co-Authors: Christian Chabrier, Celine Carles, Philippe Tixier, Pierre Francois Duyck, Patrick QueneherveAbstract:The burrowing nematode, Radopholus similis (Cobb.) Thorne, causes the most damage to bananas. To minimize nematicide applications, cropping systems that use fallow, crop rotation and clean planting material have been developed in the French West Indies. In order to optimize the benefit of the intercropping period, we studied the survivorship of R. similis in different soil types and conditions. We monitored the survivorship of calibrated populations of R. similis in the laboratory on a Nitisol and on an Andosol, two soils derived from volcanic ashes and pumices. We studied water potentials ranging from 0 to � 700 kPa on undisturbed soil and on soil previously frozen to get rid of living nematodes. Mortality of adult R. similis decreased regularly, and was fairly well described by Teissier’s model. In the previously frozen soils, R. similis survived longer in wet soils (half-life of 21–46 days at 0 to � 5 kPa) than in dry soils (half-life of less than 10 days between � 80 and � 250 kPa). In contrast, in undisturbed soils, R. similis survived longer in dry soils: half-lives ranged from 57 days at � 273 kPa to 17 days at water saturation in the Andosol, and 36 days at � 660 kPa to 14 days at water saturation in the Nitisol. These results are consistent with the absence of anhydrobiosis in R. similis, unlike Pratylenchus coffeae. P. coffeae survivorship curves over time do not follow a model derived from exponential decrease like Teissier’s model. These results also show that the recommended one year host-free period required to sanitize soils cannot be shortened without risk, even if flooding the soil could improve it.
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Survival of the burrowing nematode Radopholus similis (Cobb) Thorne without food: Why do males survive so long?
Applied Soil Ecology, 2010Co-Authors: Christian Chabrier, Yves-marie Cabidoche, Pierre Francois Duyck, Phlippe Tixier, Patrick QueneherveAbstract:The burrowing nematode Radopholus similis is the most damaging banana nematode. To minimize nematicide applications, cropping systems based on fallow, crop rotation, and using clean planting material have been developed in the French West Indies. The survivorship of R. similis in water and soil was evaluated to optimize the collapse of its populations during the intercropping period and to better understand the risk of dissemination of nematodes by run-off water. In both Andosols and Nitisols, survivorship was significantly higher for males than for females. After 180 days, 21.7% of males and 9.8% of females were still alive, whereas no juveniles survived after 150 days. Survivorship was much lower in water and soil solution than in soil. The mean half-life of males was 8.8 days and only 6.2 days for females, but the difference between sexes was less after 1 month: 8% of both males and females in the initial population survived after 35 days. These results suggest that resource allocation for males was directed towards reproduction, whereas females expend energy foraging and laying eggs, and are thus disadvantaged in the absence of host plants. The relatively long survivorship of males of R. similis enables them to fecundate females without competing for food after becoming adults.
Magalie Lesueurjannoyer - One of the best experts on this subject based on the ideXlab platform.
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soil thresholds and a decision tool to manage food safety of crops grown in chlordecone polluted soil in the french west indies
Environmental Pollution, 2017Co-Authors: Florence Clostre, Philippe Letourmy, Magalie LesueurjannoyerAbstract:Due to the persistent pollution of soils by an organochlorine, chlordecone (CLD also known as Kepone ©) in the French West Indies, some crops may be contaminated beyond the European regulatory threshold, the maximum residue limit (MRL). Farmers need to be able to foresee the risk of not complying with the regulatory threshold in each field and for each crop, if not, farmers whose fields are contaminated would have to stop cultivating certain crops in the fields concerned. To help farmers make the right choices, we studied the relationship between contamination of the soil and contamination of crops. We showed that contamination of a crop by CLD depended on the crop concerned, the soil CLD content and the type of soil. We grouped crop products in three categories: (i) non-uptakers and low-uptakers, (ii) medium-uptakers, and (iii) high-uptakers, according to their level of contamination and the resulting risk of exceeding MRL. Using a simulation model, we computed the soil threshold required to ensure the risk of not complying with MRL was sufficiently low for each crop product and soil type. Threshold values ranged from 0.02 μgkg-1 for dasheen grown in nitisol to 1.7 μgkg-1 for yam grown in andosol in the high-uptake category, and from 1 μgkg-1 for lettuce grown in nitisol to 45 μgkg-1 for the leaves of spring onions grown in andosol in the medium-uptake category. Contamination of non-uptakers and low-uptakers did not depend on soil contamination. With these results, we built an easy-to-use decision support tool based on two soil thresholds (0.1 and 1 μgkg-1) to enable growers to adapt their cropping system and hence to be able to continue farming.
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comparative fate of an organochlorine chlordecone and a related compound chlordecone 5b hydro in soils and plants
Science of The Total Environment, 2015Co-Authors: Florence Clostre, Philippe Cattan, Jeanmarie Gaude, Celine Carles, Philippe Letourmy, Magalie LesueurjannoyerAbstract:We address the problem of the comparative environmental fate of a pesticide, chlordecone (CLD), and a related compound, chlordecone-5b-hydro (CLD-5b-hydro). We used a large database including data from two types of contaminated volcanic soils, andosol and nitisol, and thirteen crops grown in the French West Indies in historically polluted soils. We performed in-depth statistical analysis of the effect of different parameters (soil type, crop, organ, etc.) on the ratio of CLD-5b-hydro to CLD in both soils and plants. The environmental fate of the two compounds differed depending on the type of soil. Proportionally, more CLD-5b-hydro than CLD was measured in Nitisols than in andosols. Compared to CLD, we also found a preferential transfer of CLD-5b-hydro from the soil to the plant. Finally, mobilization of the two compounds differed according to the species of crop but also within the plant, with increasing ratios from the roots to the top of the plant. The properties of the compound played a key role in the underlying processes. Because CLD-5b-hydro is more soluble in water and has a lower Kow than CLD, CLD-5b-hydro (1) was more easily absorbed from soils by plants, (2) was less adsorbed onto plant tissues and (3) was transported in greater quantities through the transpiration stream. Due to the amounts of CLD-5b-hydro we measured in some plant parts such as cucurbit fruits, an assessment of the toxicity of this CLD monodechlorinated product is recommended.
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soil type and growing conditions influence uptake and translocation of organochlorine chlordecone by cucurbitaceae species
Water Air and Soil Pollution, 2014Co-Authors: Florence Clostre, Celine Carles, Philippe Letourmy, Baptiste Turpin, Magalie LesueurjannoyerAbstract:Chlordecone (CLD), an organochlorine insecticide, and other persistent organic pollutants continue to contaminate the environment worldwide and have adverse effects on human health through food exposure. Cucurbitaceae take up weathered hydrophobic pollutants from the soil and translocate them to their shoots. As Cucurbitaceae are an important part of the diet in the French West Indies, they are among the main contributors to total dietary intake of CLD. We analyzed the contamination by CLDs (CLD and 5b-hydroCLD) of four cucurbits grown in the field and/or in the greenhouse. Different physiological (crop species) and environmental (soil type, growth conditions) variables were shown to influence uptake of the pollutant from the soil by the crop. Cucurbita species (zucchini and pumpkin) were more contaminated than Cucumis sativus (cucumber), and Sechium edule (christophine or chayote) translocated CLDs to fruits very poorly compared with cucumber and pumpkin. Greenhouse conditions and non-allophanic (Nitisols and ferralsols) soils favored plant contamination more than field conditions and allophanic soils (andosols).
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determination of soil content in chlordecone organochlorine pesticide using near infrared reflectance spectroscopy nirs
Environmental Pollution, 2009Co-Authors: Didier Brunet, Raphaël Achard, Luc Rangon, Thierry Woignier, Magalie Lesueurjannoyer, Bernard BarthesAbstract:Abstract Chlordecone is a toxic organochlorine insecticide that was used in banana plantations until 1993 in the French West Indies. This study aimed at assessing the potential of near infrared reflectance spectroscopy (NIRS) for determining chlordecone content in Andosols, Nitisols and Ferralsols from Martinique. Using partial least square regression, chlordecone content conventionally determined through gas chromatography–mass spectrometry could be correctly predicted by NIRS ( Q 2 = 0.75, R 2 = 0.82 for the total set), especially for samples with chlordecone content −1 or when the sample set was rather homogeneous ( Q 2 = 0.91, R 2 = 0.82 for the Andosols). Conventional measures and NIRS predictions were poorly correlated for chlordecone content >12 mg kg −1 , nevertheless ca. 80% samples were correctly predicted when the set was divided into three or four classes of chlordecone content. Thus NIRS could be considered a time- and cost-effective method for characterising soil contamination by chlordecone.
Lesueur-jannoyer Magalie - One of the best experts on this subject based on the ideXlab platform.
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Soil thresholds and a decision tool to manage food safety of crops grown in chlordecone polluted soil in the French West Indies
'Elsevier BV', 2017Co-Authors: Clostre Florence, Letourmy Philippe, Lesueur-jannoyer MagalieAbstract:Due to the persistent pollution of soils by an organochlorine, chlordecone (CLD also known as Kepone ©) in the French West Indies, some crops may be contaminated beyond the European regulatory threshold, the maximum residue limit (MRL). Farmers need to be able to foresee the risk of not complying with the regulatory threshold in each field and for each crop, if not, farmers whose fields are contaminated would have to stop cultivating certain crops in the fields concerned. To help farmers make the right choices, we studied the relationship between contamination of the soil and contamination of crops. We showed that contamination of a crop by CLD depended on the crop concerned, the soil CLD content and the type of soil. We grouped crop products in three categories: (i) non-uptakers and low-uptakers, (ii) medium-uptakers, and (iii) high-uptakers, according to their level of contamination and the resulting risk of exceeding MRL. Using a simulation model, we computed the soil threshold required to ensure the risk of not complying with MRL was sufficiently low for each crop product and soil type. Threshold values ranged from 0.02 μgkg−1 for dasheen grown in nitisol to 1.7 μgkg−1 for yam grown in andosol in the high-uptake category, and from 1 μgkg−1 for lettuce grown in nitisol to 45 μgkg−1 for the leaves of spring onions grown in andosol in the medium-uptake category. Contamination of non-uptakers and low-uptakers did not depend on soil contamination. With these results, we built an easy-to-use decision support tool based on two soil thresholds (0.1 and 1 μgkg−1) to enable growers to adapt their cropping system and hence to be able to continue farming. (Résumé d'auteur)ttttt
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Sequestering a persistent organochlorine with organic fertilizer and organic amendment to increase food safety in Martinique
s.n., 2015Co-Authors: Fernandes Paula, Clostre Florence, Woignier Thierry, Soler Alain, Rangon Luc, Lesueur-jannoyer MagalieAbstract:Chlordecone is an environmentally persistent insecticide that was intensively used in banana cropping systems. Although its use was restricted 20 years ago, chlordecone permanently pollutes soils and consequently continues to contaminate crops, water resources, and food chains. This pesticide was recently suspected of being implicated in the increasing incidence of prostate cancer and in the impaired development of young children. Given the proven risks to human health, the release of chlordecone from polluted soil needs to be controlled to reduce contamination of the different food chains. Natural decontamination of the soil through lixiviation will take decades to centuries. The persistence of chlordecone in soils is explained by i) its physicochemical properties: low solubility in water, hydrophobicity, which gives it a high affinity for organic matter and ii) its poor biodegradability related to its peculiar chemical structure with high steric hindrance. Chlordecone pollution concerns a large area, meaning chlordecone-polluted sites require efficient cost-effective in situ treatments. To date, phytoextraction and microbial degradation have not really been efficient in the case of diffuse pollution of chlordecone in the soil. Thus, sequestering chlordecone in the soil could be an alternative way to reduce its availability for crops and water resources. We then chose to study the ability of two different organic matters to sequestrate this molecule in the two main contaminated soil types presenting different characteristics: andosols, with amorphous clays (allophane), and Nitisols, with crystalline 1/1 clays. We tested two types of organic matter: an organic fertilizer and an organic amendment. For each experiment (in microcosm, in pots and at field scale), the same quantities (5% w/w) of organic fertilizer or organic amendment were incorporated into both contaminated soils. During these experiments, we measured during three months the effects of organic fertilizer and organic amendment incorporation into soil on (i) chlordecone leaching by water, (ii) chlordecone bioavailability for susceptible crops (radish, cucumber, lettuce) and contamination of their different organs (roots, tuber, fruits, leaves) (iii) chlordecone distribution in different soil fractions (0-50?m, 50-200?m, 200-2000?m), (iv) soil microstructure (pore size distribution, specific surface area, mesopore volume and nanoscale structure). A quick decrease in water extractable chlordecone was observed in amended soils and then its transfer from soils to plants. Depending on the soil and the crop, the soil-plant transfer was also reduced by a factor of 1.9 to 15 when organic matter was incorporated. Chlordecone distribution was modified by the incorporation of both organic materials leading to a transfer of the molecule from the finest to the coarser fractions according to the organic matter size distribution, thus raising a "sponge" effect, mainly observed on the nitisol, of the added organic matter on the chlordecone probably due to the high affinity to organic matter and hydrophobicity of this molecule. For the andosol, the results showed that the changes in chlordecone distribution in the different soil fractions were not as dramatic as those in the nitisol. This raises the question of the specific physical and structural properties of the allophanic clays. Considering the impact of organic matter on soil microstructure seen though the pore size distribution, after the addition of organic matter, the mesopore structure was not really affected in the nitisol, even after 3 months. These results clearly differed from those observed on andosol where the addition of compost led to a marked reduction in mesoporosity. After 90 days, the pore size distribution was still strongly affected by both composts (loss of 80% of the mesopores). Results also show a clear decrease in the specific surface area and specific mesopore volume of the andosol after addition of orga
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Comparative fate of an organochlorine, chlordecone, and a related compound, chlordecone-5b-hydro, in soils and plants
'Elsevier BV', 2015Co-Authors: Clostre Florence, Letourmy Philippe, Cattan Philippe, Gaude Jean-marie, Carles Céline, Lesueur-jannoyer MagalieAbstract:We address the problem of the comparative environmental fate of a pesticide, chlordecone (CLD), and a related compound, chlordecone-5b-hydro (CLD-5b-hydro). We used a large database including data from two types of contaminated volcanic soils, andosol and nitisol, and thirteen crops grown in the French West Indies in historically polluted soils. We performed in-depth statistical analysis of the effect of different parameters (soil type, crop, organ, etc.) on the ratio of CLD-5b-hydro to CLD in both soils and plants. The environmental fate of the two compounds differed depending on the type of soil. Proportionally, more CLD-5b-hydro than CLD was measured in Nitisols than in andosols. Compared to CLD, we also found a preferential transfer of CLD-5b-hydro from the soil to the plant. Finally, mobilization of the two compounds differed according to the species of crop but also within the plant, with increasing ratios from the roots to the top of the plant. The properties of the compound played a key role in the underlying processes. Because CLD-5b-hydro is more soluble in water and has a lower Kow than CLD, CLD-5b-hydro (1) was more easily absorbed from soils by plants, (2) was less adsorbed onto plant tissues and (3) was transported in greater quantities through the transpiration stream. Due to the amounts of CLD-5b-hydro we measured in some plant parts such as cucurbit fruits, an assessment of the toxicity of this CLD monodechlorinated product is recommended. (Résumé d'auteur
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Organochlorine (chlordecone) uptake by root vegetables
'Elsevier BV', 2015Co-Authors: Clostre Florence, Letourmy Philippe, Lesueur-jannoyer MagalieAbstract:Chlordecone, an organochlorine insecticide, continues to pollute soils in the French West Indies. The main source of human exposure to this pollutant is food. Root vegetables, which are staple foods in tropical regions, can be highly contaminated and are thus a very effective lever for action to reduce consumer exposure. We analyzed chlordecone contamination in three root vegetables, yam, dasheen and sweet potato, which are among the main sources of chlordecone exposure in food in the French West Indies. All soil types do not have the same potential for the contamination of root vegetables, allophanic andosols being two to ten times less contaminating than non-allophanic Nitisols and ferralsols. This difference was only partially explained by the higher OC content in allophanic soils. Dasheen corms were shown to accumulate more chlordecone than yam and sweet potato tubers. The physiological nature of the root vegetable may explain this difference. Our results are in good agreement with the hypothesis that chlordecone uptake by root vegetables is based on passive and diffusive processes and limited by transport and dilution during growth. (Résumé d'auteur
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Compost addition to polluted soils to ensure fruit and vegetable safety
'International Society for Horticultural Science (ISHS)', 2015Co-Authors: Lesueur-jannoyer Magalie, Clostre Florence, Fernandes Paula, Woignier ThierryAbstract:Pollution affects food safety, environmental quality and human health. ln the case of persistent soil pollution such as chlordecone in the French West Indies, horticultural crops can be so polluted as to exceed maximum residue limits. Generally, there is no remediation solution for these polluted soils. Interactions between organic matter and pesticides are known to help reduce the bioavailability of pesticides in soils. Sequestering pesticides in soils by adding compost could be an alternative way of reducing their diffusion into food chains. We added 5% organic matter to the soil upper layer in horticultural fields and pots. The soil to crop transfer for radish, lettuce and cucumber decreased from 33 to 75% according to the crop and the soil type. We demonstrated that sequestration depended on the soil type and the clay physical properties. In Nitisols, chlordecone sequestration was mainly due to chemical interactions with the compost particles whereas in andosols, it was partly due to the physical impact of the added compost (allophane collapse). Increasing soil organic matter content reduces pesticide mobility in the soil and hence its bioavailability for plants. Adding organic amendments to soils is a promising way to reduce the risk of pesticide contamination of food and thus decrease human exposure to potentially harmful chemicals