The use of plastics has increased significantly with consequent rise in the generation of wastes. Microplastics (MPs) with particle size <5 mm are produced in natural terrestrial habitats by weathering of the discarded plastic debris and therefore are likely to impact soil biota . Earthworms are the dominant soil fauna which play vital role in soil formation and decomposition of organics. Since these animals are soil feeders, MP particles contaminating soil are likely to enter in to the gut of these animals affecting their physiology. MPs have been shown to be potent adsorbents of various other pollutants such as heavy metals and agrochemicals . This study reports the effects of two MPs, polyvinyl chloride (PVC) and polypropylene (PP) alone and in combination with the pesticide monocrotophos in soil on tissue protein, lipid peroxidation (LPX), activities of lactate dehydrogenase (LDH) and catalase (CAT) of an epigeic earthworm Eudrillus eugeniae over an exposure period of 48h. Results from molecular docking and laboratory experiment confirmed that both the MPs are potent adsorbents of the pesticide and enhanced oxidative stress on the animal with significant reduction in protein, increased LPX level and enzyme activities . PP indicated significantly higher pesticide adsorption relative to PVC.
Acetylcholinesterase (AChE) biosensor technology is widely applied in the detection of organophosphate pesticides in agricultural production via the inhibition of AChE activity by organophosphates. However, the AChE electrode has some drawbacks, such as low stability and high overpotential. Combining the advantages of multiwalled carbon nanotubes (MWCNTs) and ionic liquids, we constructed a novel bienzyme electrode [Cl/iron porphyrin (FePP)-modified MWCNTs/AChE/glassy carbon electrode], which included AChE and mimetic oxidase FePP. In this electrode, FePP is covalently bound to the AChE carrier via ionic liquid for increased electrode sensitivity and stability. Under optimal conditions, this novel biosensor has a monocrotophos detection limit of 3.2 × 10 –11 mol/L and good recovery of 89–104%. After 5 weeks of storage at 4 °C, the oxidation current was 97.8% of its original value. The biosensor has high stability and sensitivity for monocrotophos detection and is a promising device for monitoring food safety.
The complete synthesis process of Cl/FePP–MWCNTs/AChE/GCE
Xiaofang Che,Yong Huang,Tianzhu Shen,Keyuan Zhong,You Wei,Guoqiang Fan,Kun Jia,Wei Yuan,Huiqiang Lu
Monosultap (Mon) is a broad-spectrum insecticide used in agricultural production to control stem borers in rice fields . Currently, little evidence shows how Mon affects notochord development in zebrafish ( Danio rerio ). In our study, zebrafish embryos were exposed to 0.25, 0.5, and 0.75 mg/L Mon to determine the effects of different concentrations of Mon on notochord development. Mon exposure reduced the body length, decreased the heart rate and hatchability, and induced notochord deformity in zebrafish. The effects of Mon exposure on the internal organization of the notochord and the structural abnormalities were determined based on histological staining of paraffinized tissue sections. Quantitative polymerase chain reaction (qPCR) and in situ hybridization findings revealed that the expression levels of genes related to notochord development ( shha, col2a, and ptch2 ) showed an increasing trend in a concentration-dependent manner. An abnormal increase of apoptosis and cell proliferation in some parts of the notochord suggested that Mon exposure could cause developmental abnormality of the notochord. This study revealed the toxicity of Mon in notochord development. Our findings provide information in assessing the risk of Mon to the ecological environment and human health.
危险品化学品经营许可证（带存储）