Forensic toxicological implication of acute fatal poisoning cases due to benfuracarb ingestion

Carbofuran self-poisoning: forensic and analytic investigations in twins and literature review

Carbofuran is a pesticide widely used in agricultural context to kill insects, mites, and flies by ingestion or contact. Along with literature review, we aimed to (i) present the clinical, autopsy, and toxicological findings of carbofuran self-poisonings in two 69-year-old twins, resulting in the death of one of them and (ii) assess carbofuran metabolite distribution using molecular networking. Quantitative analysis of carbofuran and its main metabolites (3-hydroxycarbofuran and 3-ketocarbofuran) was carried out using an original liquid chromatography-tandem mass spectrometry method on biological samples (cardiac or peripheral blood, urine, bile, and gastric contents). Toxicological analysis of post-mortem samples (twin 1) highlighted high concentrations of carbofuran and its metabolites in cardiac blood, bile, and gastric contents. These compounds were also quantified in blood and/or urine samples of the living brother (twin 2), confirming poisoning. Using molecular networking approach to facilitate visualization of mass spectrometry datasets and sample-to-sample comparisons, we detected two more metabolites (7-phenol-carbofuran and 3-hydroxycarbofuran glucuronide) in bile (twin 1) and urine (twin 2). These results highlight the value of (i) these compounds as carbofuran consumption markers and (ii) bile samples in post-mortem analysis to confirm poisoning. From an analytical point of view, molecular networking allowed the detection and interpretation of carbofuran metabolite ammonium adducts which helped to confirm their identification annotations, as well as their structural data. From a clinical point of view, the different outcomes between the two brothers are discussed. Overall, these cases provide novel information regarding the distribution of carbofuran and its metabolites in poisoning context.

Benfuracarb inhibits body growth and causes oxidative stress in zebrafish (Danio rerio)

Benfuracarb (BEN), a broad-spectrum carbamate insecticide used for crop protection, is considered toxic to humans and aquatic organisms. However, the potential risk level of BEN to aquatic organisms is still unclear. In this study, we exposed zebrafish embryos to BEN (0.08, 0.49, and 0.90 mg/L) from 3 to 96 hours post-fertilization (hpf). The results showed that BEN caused shorter body length in zebrafish larvae. The activity of superoxide dismutase (SOD) was significantly increased after BEN exposure. Furthermore, the transcription levels of marker genes associated with early embryonic development (myoD, nkx2.4b, myh6, and gh) were disrupted after BEN treatment. Taken together, the data indicate that BEN possesses developmental toxicity to zebrafish. The results provide a valuable reference for assessing BEN's potentially harmful effects on aquatic ecosystems.

Mutagenic and cytotoxic activities of benfuracarb insecticide

Benfuracarb is a carbamate insecticide used to control insect pests in vegetables and it has anti-acetylcholinesterase activity lower than other carbamates. Cytotoxic effects of benfuracarb were evaluated by using root growth inhibition (EC50), mitotic index (MI), and mitotic phase determinations on the root meristem cells of Allium cepa and mutagenic effects were determined in Salmonella typhymurium Ames test by TA98 and TA100 strains with and without metabolic activation. In Allium test, 1 % DMSO was used as negative control group and 10 ppm MMS was used as positive control group. 75 ppm concentration of benfuracarb was found as EC50. In MI and mitotic phases determination study, 37.5, 75 and 150 ppm doses of benfuracarb were used. Dose-dependent cytotoxic activity was found by root growth inhibition and MI studies. It was identified that mitotic inhibition activity of benfuracarb was higher than 10 ppm MMS. In Ames test, mutagenic activity was not observed and over 200 µg/plate of benfuracarb was determined as cytotoxic to S. typhymurium strains. Benfuracarb can be called as "mitotic inhibitor" but not called as mutagen.

Blood carbofuran concentrations in suicidal ingestion cases

We describe four fatal cases due to ingestion of carbofuran, a carbamate insecticide. Carbofuran was detected in the gastric contents using thin layer chromatography (TLC) and gas chromatography/mass spectrophotometry (GC/MS), and quantified in the blood using a gas chromatograph equipped with nitrogen-phosphorus detector (NPD). Fatal concentrations of carbofuran in blood ranged from 0.32 to 11.6 microg/ml.

Separation methods for amino group-possessing pesticides in biological samples

The separation methods for pesticides include liquid-liquid extraction, solid-phase extraction and solid-phase microextraction, gas chromatography (GC), GC-mass spectrometry (MS), GC-MS-MS, high-performance liquid chromatography (LC), LC-MS and LC-MS-MS. This review deals with each technique commonly used for extraction, chromatographic separation and detection of amino group possessing pesticides, such as diazines, triazines, carbamates, dinitroanilines and chloroacetanilides in biological samples. The methods presented for analysis of the pesticides in complicated biological matrices seem to be easily applicable to surface or groundwater in environmental chemistry.