Side Effects of Pesticides and Metabolites in Groundwater: Impact on Denitrification
The impact of two pesticides (S-metolachlor and propiconazole) and their respective main metabolites (ESA-metolachlor and 1,2,4-triazole) on bacterial denitrification in groundwater was studied. For this, the denitrification activity and the bacterial diversity of a microbial community sampled from...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Frontiers Media S.A.
2021-05-01
|
| Series: | Frontiers in Microbiology |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/articles/10.3389/fmicb.2021.662727/full |
| _version_ | 1818663457697824768 |
|---|---|
| author | Caroline Michel Nicole Baran Laurent André Laurent André Mickael Charron Catherine Joulian |
| author_facet | Caroline Michel Nicole Baran Laurent André Laurent André Mickael Charron Catherine Joulian |
| author_sort | Caroline Michel |
| collection | DOAJ |
| description | The impact of two pesticides (S-metolachlor and propiconazole) and their respective main metabolites (ESA-metolachlor and 1,2,4-triazole) on bacterial denitrification in groundwater was studied. For this, the denitrification activity and the bacterial diversity of a microbial community sampled from a nitrate-contaminated groundwater were monitored during 20 days in lab experiments in the presence or absence of pesticides or metabolites at 2 or 10 μg/L. The kinetics of nitrate reduction along with nitrite and N2O production all suggested that S-metolachlor had no or only little impact, whereas its metabolite ESA-metolachlor inhibited denitrification by 65% at 10 μg/L. Propiconazole and 1,2,4-triazole also inhibited denitrification at both concentrations, but to a lesser extent (29–38%) than ESA-metolachlor. When inhibition occurred, pesticides affected the reduction of nitrate into nitrite step. However, no significant differences were detected on the abundance of nitrate reductase narG and napA genes, suggesting an impact of pesticides/metabolites at the protein level rather than on denitrifying bacteria abundance. 16S rRNA gene Illumina sequencing indicated no major modification of bacterial diversity in the presence or absence of pesticides/metabolites, except for ESA-metolachlor and propiconazole at 10 μg/L that tended to increase or decrease Shannon and InvSimpson indices, respectively. General growth parameters suggested no impact of pesticides, except for propiconazole at 10 μg/L that partially inhibited acetate uptake and induced a decrease in microbial biomass. In conclusion, pesticides and metabolites can have side effects at environmental concentrations on microbial denitrification in groundwater and may thus affect ecosystem services based on microbial activities. |
| first_indexed | 2024-12-17T05:17:09Z |
| format | Article |
| id | doaj.art-736e77be44cd4dbeba6dd2f4280f668f |
| institution | Directory Open Access Journal |
| issn | 1664-302X |
| language | English |
| last_indexed | 2024-12-17T05:17:09Z |
| publishDate | 2021-05-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Microbiology |
| spelling | doaj.art-736e77be44cd4dbeba6dd2f4280f668f2022-12-21T22:02:05ZengFrontiers Media S.A.Frontiers in Microbiology1664-302X2021-05-011210.3389/fmicb.2021.662727662727Side Effects of Pesticides and Metabolites in Groundwater: Impact on DenitrificationCaroline Michel0Nicole Baran1Laurent André2Laurent André3Mickael Charron4Catherine Joulian5BRGM, DEPA (Direction de l’Eau, de l’Environnement, des Procédés et Analyses), Orléans, FranceBRGM, DEPA (Direction de l’Eau, de l’Environnement, des Procédés et Analyses), Orléans, FranceBRGM, DEPA (Direction de l’Eau, de l’Environnement, des Procédés et Analyses), Orléans, FranceUniversité d’Orléans, CNRS, BRGM, UMR 7327 Institut des Sciences de la Terre d’Orléans, Orléans, FranceBRGM, DEPA (Direction de l’Eau, de l’Environnement, des Procédés et Analyses), Orléans, FranceBRGM, DEPA (Direction de l’Eau, de l’Environnement, des Procédés et Analyses), Orléans, FranceThe impact of two pesticides (S-metolachlor and propiconazole) and their respective main metabolites (ESA-metolachlor and 1,2,4-triazole) on bacterial denitrification in groundwater was studied. For this, the denitrification activity and the bacterial diversity of a microbial community sampled from a nitrate-contaminated groundwater were monitored during 20 days in lab experiments in the presence or absence of pesticides or metabolites at 2 or 10 μg/L. The kinetics of nitrate reduction along with nitrite and N2O production all suggested that S-metolachlor had no or only little impact, whereas its metabolite ESA-metolachlor inhibited denitrification by 65% at 10 μg/L. Propiconazole and 1,2,4-triazole also inhibited denitrification at both concentrations, but to a lesser extent (29–38%) than ESA-metolachlor. When inhibition occurred, pesticides affected the reduction of nitrate into nitrite step. However, no significant differences were detected on the abundance of nitrate reductase narG and napA genes, suggesting an impact of pesticides/metabolites at the protein level rather than on denitrifying bacteria abundance. 16S rRNA gene Illumina sequencing indicated no major modification of bacterial diversity in the presence or absence of pesticides/metabolites, except for ESA-metolachlor and propiconazole at 10 μg/L that tended to increase or decrease Shannon and InvSimpson indices, respectively. General growth parameters suggested no impact of pesticides, except for propiconazole at 10 μg/L that partially inhibited acetate uptake and induced a decrease in microbial biomass. In conclusion, pesticides and metabolites can have side effects at environmental concentrations on microbial denitrification in groundwater and may thus affect ecosystem services based on microbial activities.https://www.frontiersin.org/articles/10.3389/fmicb.2021.662727/fulldenitrificationgroundwaterchloroacetanilideconazolepesticidesmetabolites |
| spellingShingle | Caroline Michel Nicole Baran Laurent André Laurent André Mickael Charron Catherine Joulian Side Effects of Pesticides and Metabolites in Groundwater: Impact on Denitrification Frontiers in Microbiology denitrification groundwater chloroacetanilide conazole pesticides metabolites |
| title | Side Effects of Pesticides and Metabolites in Groundwater: Impact on Denitrification |
| title_full | Side Effects of Pesticides and Metabolites in Groundwater: Impact on Denitrification |
| title_fullStr | Side Effects of Pesticides and Metabolites in Groundwater: Impact on Denitrification |
| title_full_unstemmed | Side Effects of Pesticides and Metabolites in Groundwater: Impact on Denitrification |
| title_short | Side Effects of Pesticides and Metabolites in Groundwater: Impact on Denitrification |
| title_sort | side effects of pesticides and metabolites in groundwater impact on denitrification |
| topic | denitrification groundwater chloroacetanilide conazole pesticides metabolites |
| url | https://www.frontiersin.org/articles/10.3389/fmicb.2021.662727/full |
| work_keys_str_mv | AT carolinemichel sideeffectsofpesticidesandmetabolitesingroundwaterimpactondenitrification AT nicolebaran sideeffectsofpesticidesandmetabolitesingroundwaterimpactondenitrification AT laurentandre sideeffectsofpesticidesandmetabolitesingroundwaterimpactondenitrification AT laurentandre sideeffectsofpesticidesandmetabolitesingroundwaterimpactondenitrification AT mickaelcharron sideeffectsofpesticidesandmetabolitesingroundwaterimpactondenitrification AT catherinejoulian sideeffectsofpesticidesandmetabolitesingroundwaterimpactondenitrification |