Understanding and addressing microplastic pollution: Impacts, mitigation, and future perspectives.

Improper disposal of household and industrial waste into water bodies has transformed them into de facto dumping grounds. Plastic debris, weathered on beaches degrades into micro-particles and releases chemical additives that enter the water. Microplastic contamination is documented globally in both marine and freshwater environments, posing a significant threat to aquatic ecosystems. The small size of these particles makes them susceptible to ingestion by low trophic fauna, a trend expected to escalate. Ingestion leads to adverse effects like intestinal blockages, alterations in lipid metabolism, histopathological changes in the intestine, contributing to the extinction of vulnerable species and disrupting ecosystem balance. Notably, microplastics (MPs) can act as carriers for pathogens, potentially causing impaired reproductive activity, decreased immunity, and cancer in various organisms. Studies have identified seven principal sources of MPs, including synthetic textiles (35%) and tire abrasion (28%), highlighting the significant human contribution to this pollution. This review covers various aspects of microplastic pollution, including sources, extraction methods, and its profound impact on ecosystems. Additionally, it explores preventive measures, aiming to guide researchers in selecting techniques and inspiring further investigation into the far-reaching impacts of microplastic pollution, fostering effective solutions for this environmental challenge.

Assessing organophosphate insecticide retention in muscle tissues of juvenile common carp fish under acute toxicity tests.

Organophosphate insecticide spray poses potential threat of contamination of environmental components their accumulation in aquatic organisms. Although various physiological deficits associated with their exposure in fishes are documented, yet their retention in their edible muscle tissues has been poorly studied. In this context, the study was undertaken to ascertain the bioaccumulation of two organophosphate insecticide compounds (dimethoate and chlorpyrifos) in the muscles of juvenile Cyprinus carpio. The study could provide insight into the risks to human health associated with consuming contaminated fish flesh. The fishes exposed to various concentrations of dimethoate and chlorpyrifos in-vivo for 96 to ascertain the uptake and retention of these insecticides in the muscle. Results indicated that fish muscles accumulated the residues at all the concentrations with the recovery of 2.99% (0.032 ppm) of dimethoate exposed to LC50 concentrations. In contrast, the chlorpyrifos residues were found Below the Detection Level (BDL) in the fishes exposed to LC50 concentrations. The percentage bioaccumulation of dimethoate in fish muscle was 88.10%, and that of chlorpyrifos was BDL. The bio-concentration factor was dose-dependent and increased with increasing doses of both insecticides. The study invites attention to human health risk assessment in the regions where contaminated fish are consumed without scientific supervision.

Behavioural incongruities in juvenile Cyprinus carpio exposed to organophosphate compounds.

For the ever increasing human population, the necessity to produce the food in large quantities has become the main goal internationally which has led to increase the practice of pesticides globally. Presence of pesticides in aquatic water bodies is largely due to the runoff from agricultural fields causing to deteriorate the healthy characteristics of an aquatic environment system leading to the toxic impact on non-target aquatic organism such as fish. Approach: In fish, there are various portal of entry through which the contaminants enter. Via various routes, the contaminants reach into the blood and subsequently to different organs or systems. Since Pesticides are known to modify the behavior of animals when exposed to toxic levels. The behavioral changes may be caused by the changes in the nervous system triggered directly or through metabolic or physiological activities. However, the effects have been found to be multifarious and known to differ at different concentrations. Also, Blood is the most accessible component of the vertebrate body fluid system and consequences of direct and indirect damage to blood cells and their precursors are predictable and potentially life threatening. Therefore, behavioural and genotoxicological studies have been considered and used as diagnostic tool in order to investigate behavioural and genotoxicological alterations. This study was undertaken to investigate behavioural changes in Cyprinus carpio exposed to two organophosphate compounds, chlorpyrifos (cpf) and dimethoate (dim). Fishes weighing 10 ± 2 g were exposed to sub-lethal concentrations of cpf (0.76 ppb, 1.52 ppb, 2.28 ppb, 3.04 ppb and 3.8 ppb) and dimethoate (0.22 ppm, 0.44 ppm, 0.66 ppm, 0.88 ppm and 1.1 ppm) for the period of 96 h and various behavioural indices were evaluated during that period. Both the pesticides were found to induce behavioral toxicity in fishes such as drop in swimming velocity, reduced swimming activity and retarded opercular movements. Cpf was found more detrimental as compared to dimethoate in all cases. Fishes also elicited a genotoxic response which was evaluated by calculating the frequency of micronuclei formation in their hematocytes after 21 days of exposure. Chlorpyrifos induced more genotoxicity than dimethoate which was found dose and time dependent. Conclusion: It was concluded that the behavioural and genotoxic alterations in common carp could be applied as possible biomarkers in risk assessment and monitoring programs for pesticide contamination of aquatic ecosystems. Contribution: This study is one of its kind and will help to form baseline data.