Brain cancer and pesticide relationship in orchard farmers of Kashmir

Alkylating agents are possible inducers of glioblastoma and other brain tumors

Epidemiological evidence of an association between exposure to chemical carcinogens and an increased risk for development of glioblastoma (GBM) is limited to weak statistical associations in cohorts of firefighters, farmers, residents exposed to air pollution, and soldiers exposed to toxic chemicals (e.g., military burn pits, oil-well fire smoke). A history of ionizing radiation therapy to the head or neck is associated with an increased risk of GBM. Ionizing radiation induces point mutations, frameshift mutations, double-strand breaks, and chromosomal insertions or deletions. Mutational profiles associated with chemical exposures overlap with the broad mutational patterns seen with ionizing radiation. Data on 16 agents (15 chemicals and radio frequency radiation) that induced tumors in the rodent brain were extracted from 602 Technical Reports on 2-years cancer bioassays found in the National Toxicology Program database. Ten of the 15 chemical agents that induce brain tumors are alkylating agents. Three of the 15 chemical agents have idiosyncratic structures and might be alkylating agents. Only two of the 15 chemical agents are definitively not alkylating agents. The rat model is thought to be of possible relevance to humans suggesting that exposure to alkylating chemicals should be considered in epidemiology studies on GBM and other brain tumors.

Time for Re-Evaluating the Human Carcinogenicity of Ethylenedithiocarbamate Fungicides? A Systematic Review

Background. In January 2021, the European Union ended the license of Mancozeb, the bestselling ethylenedithiocarbamate (EBDC) fungicide, because of some properties typical of human carcinogens. This decision contrasts the IARC classification of EBDC fungicides (Group 3, not classifiable as to human carcinogenicity). A systematic review of the scientific literature was conducted to explore the current evidence. Methods. Human and experimental studies of cancer and exposure to EBDC fungicides (Mancozeb, Maneb, Zineb, and others) and ethylene thiourea (ETU), their major metabolite, published in English as of December 2021, were retrieved using PubMed, the list of references of the relevant reports, and grey literature. Results. The epidemiological evidence of EBDC carcinogenicity is inadequate, with two studies each suggesting an association with melanoma and brain cancer and inconsistent findings for thyroid cancer. Experimental animal studies point at thyroid cancer in rats and liver cancer in mice, while multiple organs were affected following the long-term oral administration of Mancozeb. The mechanism of thyroid carcinogenesis in rats has also been shown to occur in humans. Genotoxic effects have been reported. Conclusions. The results of this systematic review suggest inadequate evidence for the carcinogenicity of EBDC fungicides from human studies and sufficient evidence from animal studies, with positive results on three out of ten key characteristics of carcinogens applying to humans as well. An IARC re-evaluation of the human carcinogenicity of EBDC fungicides is warranted.

Impacts of Erratic Snowfall on Apple Orchards in Kashmir Valley, India

Kashmir Valley has been witnessing erratic snowfall events in recent autumns which severely impacted apple orchards and harvests. Here, we combine remotely sensed data and field observations to map snowfall distribution and snow depths during the recent snowfall events in November 2018 and November 2019. Besides, we used ERA-5 reanalysis climate datasets to investigate the causes of these erratic snowfall events, pointing to an early arrival of Western Disturbances (WD) to the area. Analysis of these untimely snowfall episodes indicates that snow depths varied from 5–122 cm and 31–152 cm during the 2018 and 2019 snowfall events, respectively. In turn, satellite data analysis reveals that the apple orchards cover roughly 9.8% (1329 km2) of the entire surface of Kashmir Valley, out of which 32.6% were mildly to severely damaged by snow. The areas in South Kashmir suffered the most from the untimely snowfall with an area affected estimated to ~264 km2, followed by North Kashmir (~151 km2) and Central Kashmir (18 km2). The snowfall caused substantial harvest losses in orchards ranging from 4–50% with an average of ~35%. The geopotential analysis from the ERA-5 dataset provides insights into the synoptic weather patterns leading to the snowfall events and point to a trough in the high-troposphere (200 mb), along with a col at lower levels (850 mb) over the Kashmir Valley from November 2–5, 2018. The lower levels (850 mb) experienced intense cyclonic circulation which favored advection of moisture from the Arabian Sea during the November 6–7, 2019, snowfall event. The large economic losses related to early arrival of WD led to a virtual grounding of the horticultural sector in 2018 and 2019. Therefore, more baseline research is critically needed along with a comprehensive evaluation of the suitability of horticulture as an economically viable sector that is being promoted over the Kashmir region, also under climate change.

Health risk assessment of pesticide residues in fruits and vegetables from farms and markets of Western Indian Himalayan region

The extensive use of pesticides in agriculture has become a very common practice in developing countries like India. Consequently, the increased concentration of residues of these hazardous pesticides in fruits and vegetables is manifested. The study aimed to assess the health hazards associated with the presence of pesticide residues in fruits and vegetables sampled from farms and markets of Kinnaur district of Himachal Pradesh (India). Residues of predominant pesticides used in the region, belonging to the group of organophosphates, pyrethroid and phthalimide, were analysed using gas chromatograph quadrupole mass spectrometer (GC-MS/MS). The pesticide extraction from the matrix was done following the modified QuEChERS method. Results indicated varying concentrations of pesticide residue in market and farm samples with farm samples more contaminated than market samples. Chronic health hazards prediction indicated that organophosphorus groups (methyl parathion and triazophos) posed health risk to children in the study area.

Dimethoate Induced Behavioural Changes in Juveniles of Cyprinus carpio var. communis under Temperate Conditions of Kashmir, India

The present study was designed to investigate acute toxicity of dimethoate on juvenile Cyprinus carpio var. communis. Fishes weighing 10 ± 2 gms were selected and mortality data was statistically evaluated by Finney's Probit Method. The 96-hour LC₅₀ value for Cyprinus carpio was found as 1.1 ppm in static bioassay system. Mean values of physicochemical parameters of aquarium waters determined during bioassay depicted slight variation indicating that the mortality in aquarium fishes occurred due to pesticide exposure and not suffocation. Lab. temperature ranged from 12 to 13°C; water temperature ranged from 11 to 12°C; dissolved oxygen ranged from 3.90 to 4.56 mg/L; pH ranged from 6.90 to 7.05; total dissolved solids ranged from 2.66 to 3.0 × 10³ mg/L, while CO₂ remained at a constant value of 2.0 mg/L. The fishes elicited various behavioural responses such as uncoordinated movements, convulsions, excessive mucus secretion, and imbalanced swimming which ended in a collapse to the bottom of the aquarium. Prior to death, the clinical signs like scale erosion, pale body colour, and hemorrhagic patches over the body were noticed which became more vivid up to the termination of experiments. Results of the study indicate potential toxicity of dimethoate in fingerlings of common carp for which the natural waterbodies must be continuously monitored to reduce its impact across food chains.

Cytogenetic effects of three commercially formulated pesticides on somatic and germ cells of Allium cepa

Cytological effects of Endosri-ES (endosulfan), Nuvan-NU (dichlorvos), and Kvistin-KS (carbendazim) were evaluated on mitotic and meiotic cells of Allium cepa. Test concentrations were chosen by calculating EC50 values of formulated ES, NU, and KS, which turned to be 60, 200, and 500 ppm (parts per million), respectively. Cytological studies were undertaken on root meristem cells of A. cepa using EC50, 1/2 × EC50, and 2 × EC50 of these pesticides for 24 and 48 h. Similarly, a meiotic study was conducted by applying the pesticides at the aforesaid concentrations from seedling to bud stage. A set of onion bulbs exposed to tap water was run parallel for negative control and maleic hydrazide (112.09 ppm) as positive control. During the study period, mitotic index (MI) decreased at all the pesticide concentrations compared to the negative control. Among various chromosomal aberrations, chromatin bridges, breaks, stickiness, laggard, vagrant chromosomes, fragments, C-mitosis, multipolarity, ring chromosome as well as micronuclei were observed in mitotic preparations. In contrast, meiotic aberrations revealed comparatively less frequency of chromosomal aberrations and the most frequent were lagging chromosome, stray bivalents, secondary association, chromatin bridge, disturbed anaphase, and stickiness. Comparative analysis of the pesticides showed that NU was highly toxic to plant cells than KS, while as ES showed intermediate effects between the two. Further, our study revealed that all the three pesticides produce genotoxic effects which can cause health risks to the human populations. Graphical Abstract ᅟ.

Anti-genotoxic role of eicosapentaenoic acid against imazalil-induced DNA damage in vitro

Eicosapentaenoic acid (EPA) is a polyunsaturated n-3 fatty acid and is essential to the health of mammals. Recent data show that EPA can act as anti-mutagenic agent. On the other hand, pesticides comprise a new and important class of environmental pollutants nowadays. Imazalil (IMA), a commonly used fungicide in both agricultural and clinical domains is suspected to produce very serious toxic effects in vertebrates. The present study investigated the anti-genotoxic effect of EPA against the genotoxic damage induced by IMA on cultured human lymphocytes using chromosomal aberration (CA) and micronucleus (MN) tests as cytogenetic endpoints. Peripheral blood cells were treated in vitro with varying concentrations of EPA (2.5, 5, 10, 20 and 40 μg/ml), tested in combination with IMA (336 μg/ml). Our results revealed that the rates of CAs and MNs in lymphocytes were significantly (p < 0.05) increased by IMA as compared to the controls. The results also showed that EPA alone was not genotoxic. Moreover, when combined with IMA treatment, EPA reduced the frequencies of CAs and MNs. A clear dose-dependent decrease in the genotoxic damage of IMA was observed, suggesting a genoprotective role of EPA. In conclusion, our data may have an important application for the protection of cultured human lymphocyte from the genetic damage and repercussions induced by agricultural and industrial chemicals hazardous in people.