Use of pesticides is usually related to overproduction of crops in order to overcome worldwide demand of food and alimentary safety. Nevertheless, pesticides are environmental persistent molecules, such as the organochlorine pesticides, which are often found in undesired places. In this work, we show that a hybrid nanomaterial (laccase-MSU-F) readily oxidizes the pesticide dichlorophen, reducing its acute genotoxicity and apoptotic effects. In order to predict chronic alterations related to endocrine disruption, we compared the calculated affinity of dichlorophen oxidized subproducts to steroid hormone nuclear receptors (NRs), using molecular simulation methods. We found a reduction in theoretical affinity of subproducts of oxidized dichlorophen for the ligand-binding pocket of NRs (∼5 kcal/mol), likewise of changes in binding modes, that suggests a reduction in binding events (RMSD values < 10 Å).

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The frequency of micro nucleated erythrocytes in peripheral blood of the desert pupfish (Cyprinodon macularius) from a geothermal effluent pond is determined and compared to organisms kept in an aquarium. The frequency of micronucleated erythrocytes found in pupfish from the geothermal pond is 2.75 (±2.09) and only 0.44 (±0.52) in captivity organisms. Dissolved As in the ponds doubles the 340 µg L US-EPA acute quality criteria for aquatic life and Hg equals the 1.77 µg L chronic criteria. The organisms with high MNE also have significantly high Se, As and Hg concentrations in muscle and liver. Compared to international maximum allowable limits for fish consumption, there is 81× enrichment for Se, 6× for As and 5× for Hg. Although Se is not significantly enriched in water, it is likely that its bioaccumulation occurs via feeding of detritus. The desert pupfish has a significant resistance to extreme metal accumulations and to recover under unpolluted conditions.

Introduction: Dental surgeons and technicians are continuously exposed to agents could be affect the genetic material and induce mutations. The aim of this study was to evaluate the genotoxic and cytotoxic occupational risk of dental surgeons and technicians through the micronucleated cells (MNC) and nuclear abnormalities (NA) assay in oral mucosa.Methods: Case-control study. We have collected a buccal mucosa from dental surgeons, dental technicians and healthy individuals (matched by BMI, age and gender). The smears were fixed (ethanol 80%/48 h), stained (orange acridine) and analyzed (microscope, 100×). The frequency of MNC and NA (binucleated cells [BNC], lobulated nucleus [LN], condensed chromatins [CC], karyorrhexis [KR], pyknosis (PN) and karyolysis [KL] were counted in 2,000 cells per participant.Results: 90 samples were collected (26 surgeons, 19 technicians and 45 controls). Compared with controls, exception of PN, in surgeons was higher frequency and positive association of MNC and all NA (p<0.05). Technicians were higher frequency of MNC, BNC, CC, KR and CD (p<0.05). Conclusion:The dental surgeons and technicians have genotoxic and cytotoxic damage, demonstrated by MNC and NA, which are related to an increase risk of cancer, chronic degenerative diseases and premature aging. It is necessary to improve biosecurity actions and implement routine genotoxic risk detection methods.