Components of Banisteriopsis caapi, a Plant Used in the Preparation of the Psychoactive Ayahuasca, Induce Anti-Inflammatory Effects in Microglial Cells.

Banisteriopsis caapi is used to prepare the psychoactive beverage ayahuasca, and both have therapeutic potential for the treatment of many central nervous system (CNS) conditions. This study aimed to isolate new bioactive compounds from B. caapi extract and evaluate their biological activity, and that of the known ß-carboline components of the plant (harmine, harmaline, and tetrahydroharmine), in BV-2 microglial cells, the in vivo activation of which is implicated in the physiopathology of CNS disorders. B. caapi extract was fractionated using semipreparative liquid chromatography (HPLC-DAD) and the exact masses ([M + H]+m/z) of the compounds in the 5 isolated fractions were determined by high-resolution LC-MS/MS: F1 (174.0918 and 233.1289), F2 (353.1722), F3 (304.3001), F4 (188.1081), and F5 (205.0785). Harmine (75.5-302 µM) significantly decreased cell viability after 2 h of treatment and increased the number of necrotic cells and production of reactive oxygen species at equal or lower concentrations after 24 h. F4 did not impact viability but was also cytotoxic after 24 h. Most treatments reduced proinflammatory cytokine production (IL-2, IL-6, IL-17, and/or TNF), especially harmaline and F5 at 2.5 µM and higher concentrations, tetrahydroharmine (9.3 µM and higher), and F5 (10.7 µM and higher). The results suggest that the compounds found in B. caapi extract have anti-inflammatory potential that could be explored for the development of treatments for neurodegenerative diseases.

Pesticides in surface freshwater: a critical review.

The objective of this study was to critically review studies published up to November 2021 that investigated the presence of pesticides in surface freshwater to answer three questions: (1) in which countries were the studies conducted? (2) which pesticides are most evaluated and detected? and (3) which pesticides have the highest concentrations? Using the Prisma protocol, 146 articles published from 1976 to November 2021 were included in this analysis: 127 studies used grab sampling, 10 used passive sampling, and 9 used both sampling techniques. In the 45-year historical series, the USA, China, and Spain were the countries that conducted the highest number of studies. Atrazine was the most evaluated pesticide (56% of the studies), detected in 43% of the studies using grab sampling, and the most detected in passive sampling studies (68%). The compounds with the highest maximum and mean concentrations in the grab sampling were molinate (211.38 µg/L) and bentazone (53 µg/L), respectively, and in passive sampling, they were oxyfluorfen (16.8 µg/L) and atrazine (4.8 µg/L), respectively. The levels found for atrazine, p,p'-DDD, and heptachlor in Brazil were higher than the regulatory levels for superficial water in the country. The concentrations exceeded the toxicological endpoint for at least 11 pesticides, including atrazine (Daphnia LC50 and fish NOAEC), cypermethrin (algae EC50, Daphnia and fish LC50; fish NOAEC), and chlorpyrifos (Daphnia and fish LC50; fish NOAEC). These results can be used for planning pesticide monitoring programs in surface freshwater, at regional and global levels, and for establishing or updating water quality regulations.

Toxicity of ayahuasca after 28 days daily exposure and effects on monoamines and brain-derived neurotrophic factor (BDNF) in brain of Wistar rats.

Ayahuasca is a hallucinogenic beverage that affects the serotonergic system and have therapeutic potential for many diseases and disorders, including depression and drug addiction. The objectives of this study were to evaluate the potential toxic effects of ayahuasca on rats after chronic exposure, and the levels of monoamines, their metabolites and the brain-derived neurotrophic factor (BDNF) in the brain. Female and male rats were treated orally for 28 days with H2O (control), fluoxetine (FLX), a selective serotonin reuptake inhibitor antidepressant, or ayahuasca (Aya) at doses of 0.5X, 1X and 2X the ritualistic dose (7 to 10 animals/group). Clinical, hematological and macroscopic results showed that ayahuasca was safe to the rats. Behavior tests conducted one hour after the last treatment showed that male rats from the Aya1 group explored the open field central area less than the control group, and the number of entries in the central area compared to total locomotion was also significantly lower in this group and in the FLX group. The hippocampus was removed for BDNF analysis and the remaining brain was used for monoamine analysis by HPLC-FL. Serotonin levels were significantly higher than control only in the Aya2 female group, while a significant reduction of its metabolite 5-HIAA was observed in the FLX group. Dopamine levels were similar among the experimental groups, but the levels of its metabolite DOPAC increased significantly in the Aya1 and Aya2 groups compared to controls, especially in females, and the DOPAC/dopamine turnover was significantly higher in Aya2 group. The levels of HVA, another dopamine metabolite, did not change with the treatments compared to controls, but HVA/DOPAC ratio was significantly lower in all ayahuasca male groups. Norepinephrine was not detected in any brain sample, and the levels of its metabolite MHPG did not change significantly among the groups. BDNF levels in the hippocampus were significantly higher in the FLX and Aya2 female groups compared to controls when expressed in relation to the total brain weight. The mechanisms involved in the increase in serotonin, dopamine turnover and BDNF levels observed in ayahuasca treated animals should be further investigated in specific brain areas.

Two health information systems to characterize poisoning in Brazil-a descriptive study.

BACKGROUND: Poisoning is a worldwide public health problem that involves individuals of all ages and a wide range of chemicals. This study investigated the data from two health information systems to characterize poisoning events in the Federal District (DF), Brazil. METHODS: Data related to the period from 2009 to 2013 were obtained from the poison information center (Centro de Informação Toxicológica, CIT) and the Notifiable Diseases Information System (Sistema Nacional de Agravos de Notificação, SINAN) of the DF. RESULTS: A total of 3622 cases were reported to CIT-DF and 5702 cases to SINAN-DF. Most of the cases in CIT-DF (53%) occurred with children up to 9 years old, while this corresponded to 33.9% in SINAN-DF. Unintentional poisoning was the main circumstance involved in the cases. Pharmaceuticals were the main agent (44.3-47.1% of the cases), mainly clonazepan and paracetamol, and pesticides the most fatal (2.4% fatality rate). Out of the 47 fatal cases reported to the systems, only four were reported to both; six cases occurred with children up to 6 years. CONCLUSION: Under-reporting and missing information were identified in both systems, but the data were complementary to describe the epidemiology of poisoning cases in the DF.

Arsenic, lead, mercury and cadmium: Toxicity, levels in breast milk and the risks for breastfed infants.

Metals are ubiquitous in nature, being found in all environmental compartments, and have a variety of applications in human activities. Metals are transferred by maternal blood to the fetus via the placenta, and exposure continues throughout life. For the general population, exposure comes mainly from water and food consumption, including breast milk. In this paper, we reviewed studies on the toxicity of arsenic, lead, mercury and cadmium, the toxic metals of most concern to human health, focusing on the potential risks to newborns and infants. A total of 75 studies published since 2000 reporting the levels of these metals in breast milk were reviewed. Lead was the metal most investigated in breast milk (43 studies), and for which the highest levels were reported (up to 1515µg/L). Arsenic was the least investigated (18 studies), with higher levels reported for breast milk (up to 149µg/L) collected in regions with high arsenic concentrations in water (>10µg/L). Data from 34 studies on mercury showed that levels in breast milk were generally higher in populations with high fish consumption, where it may be present mainly as MeHg. Cadmium levels in breast milk were the lowest, with means <2µg/L in most of the 29 studies reviewed. Results of risk assessments indicated that the intake of arsenic, lead and mercury by infants through breastfeeding can be considered a health concern in most regions of the world. Although the potential risks to infants are mostly outweighed by the benefits of breast milk consumption, it is essential that contaminants be continuously monitored, especially in the most critical regions, and that measures be implemented by health authorities to reduce exposure of newborns and infants to these metals, and thus avoid unnecessary health risks.

Dietary supplements: International legal framework and adulteration profiles, and characteristics of products on the Brazilian clandestine market.

The objectives of this work were to evaluate current legislation on dietary supplements in the United States, the European Union and Brazil, and the profile of adulterated and/or irregular products on these markets. Due to a less restrictive legal framework, a supplement product that is freely available in the US may be considered a drug or even be proscribed in the EU and Brazil, thus giving rise to a clandestine market based on smuggling. From 2007 to 2014, the United States Food and Drug Administration reported 572 cases of supplement adulterations in the country, mainly products for sexual enhancement (41.6%). Data from the European Union Rapid Alert System for Food and Feed showed 929 adulterations during the same period, over 40% due to unauthorized ingredients or undeclared medicines. From 2007 to 2013, the Brazilian Federal Police Department seized 5470 supplement products, 92.2% with an American-declared origin. Qualitative chemical analyses performed on 2898 products found 180 adulterations, 41.1% due to undeclared drugs, mainly anabolic steroids, anorectics and products for erectile dysfunction, all considered medicines in Brazil. Educating the public regarding the potential risks they are taking when consuming adulterated or irregular products is necessary to protect the health of consumers.

Determination of ethylene-bis-dithiocarbamates and their degradation product ethylenethiourea in dry herbs by UHPLC-MS/MS.

Dithiocarbamates are a class of fungicides widely used in many countries. In this study, methods for determining the ethylene-bis-dithiocarbamate (EBDC) subclass, and their degradation product ethylenethiourea (ETU) were validated by UHPLC-MS/MS in different types of dry herbs, which can be used as food and/or medicinal purposes. Mancozeb was used in the validation of the EBDC method, where it was initially complexed with EDTA, derivatized, extracted with dimethyl sulfate in acetonitrile, magnesium sulfate (MgSO4), and sodium chloride (NaCl), and then purified using primary secondary amine (PSA). In the ETU method, L-cysteine hydrochloride monohydrate was added to the samples before extraction with acetonitrile, MgSO4, and NaCl, followed by purification with PSA. A pesticide-free blend of seven herbs (boldo, artichoke, "espinheira-santa", cat's claw, senna, chamomile, and cascara buckthorn) comprising distinct parts of the plants (leaves, bark, flowers and/or stems) was used as a control for method validation. Recoveries ranged from 79 to 113% for EBDC and 81 to 109% for ETU. Repeatability and intermediate precision were <20% for both methods. The limit of quantification was 0.03 mg kg-1 for EBDC (0.02 mg kg-1 of CS2) and ETU. The limit of detection (LOD) was set at 1/3 of the LOQ (0.01 mg kg-1 for both analytes). In total, 103 samples of 33 different dry herbs were analyzed, of which 19.4% were positive for EBDC (≥LOD), but no ETU residues were found in any of the analyzed samples. Given the absence of registered dithiocarbamates for use in the investigated herbs in Brazil, the positive results suggest potential illegal pesticide use or cross-contamination, especially considering the low concentrations detected in most samples. Although exposure to EBDC through the consumption of medicinal herbs from positive samples did not indicate a health risk to consumers, these plants must be monitored to prevent illicit pesticide usage, particularly when the herbs are intended for therapeutic purposes.

Target analysis of psychoactive drugs in oral fluid by QuEChERS extraction and LC-MS/MS.

This study aimed to validate a modified QuEChERS method, followed by liquid chromatography-tandem mass spectrometry, for the determination of 51 psychoactive substances and screening of 22 ones in oral fluid from electronic dance music party (EDM) attendees. Unstimulated oral fluid was collected in a polypropylene tube and stored in a glass vial at -20 ºC. The sample was extracted with acetonitrile:water and MgSO4/NaOAc, followed by cleanup with primary secondary amine and MgSO4. The effectiveness of the sample storage conditions was shown to be comparable to when the Quantisal™ buffer was used, with no substantial concentration loss (< 15%) for all the substances after up to 72 hours at -20º C. The method was satisfactorily validated, with limits of detection (LOD) and quantification (LOQ) ranging from 0.04 to 0.5 ng/mL and 0.1-1.5 ng/mL, respectively, and was applied to the analysis of 62 real samples. The main substances detected were 3,4-methylenedioxymethamphetamine (MDMA) (<0.5-829 ng/mL) and/or methylenedioxyamphetamine (MDA) (10.1 - 460.6 ng/mL), found in 27 samples, and cocaine (13.0-407.3 ng/mL) and its metabolites (benzoylecgonine 0.17-214.1 ng/mL; ecgonine methyl ester 1.8-150.1 ng/mL) in eight samples. Methamphetamine (11-439 ng/mL) was detected in eight samples, along with MDMA and MDA; eutylone was detected in two cases (4.7 and 24.1 ng/mL) reported as "ecstasy" ingestion. A comparison between self-reported drug use and results of oral fluid analysis indicated that the use of illicit substances is often underreported among EDM attendees, who are often unaware of the substances they consume.

Consumers' Trust in Different Sources of Information Related to Food Hazards and Their Judgment of Government Performance-A Cross-Sectional Study in Brazil.

Trust in institutions is fundamental for the stability and proper functioning of democracies, particularly in matters of high public sensitivity, such as food safety. This study aimed to assess trust levels in different sources of information and respondents' evaluation of the performance of government agencies responsible for controlling food-related hazards. Individuals interviewed in three environments (hospitals/clinics, supermarkets, universities, N = 1000) answered a face-to-face questionnaire in the Federal District of Brazil, and another population (health surveillance employees at the municipal, state and federal levels; N = 1017) answered the questionnaire online. About 60% of the population interviewed considered government performance to be low/very low. Scientists/universities, medical doctors (MD)/health professionals, and nongovernmental organizations (NGOs) were judged to be the most reliable sources of information on food hazards, while the food industry, supermarkets and social media inspired the lowest trust. Individuals from the hospitals/clinics group had significantly higher trust in MD/health professionals, media and websites than the two other Federal District groups. In general, income and education were the most predictive factors for the results, being negatively associated with assessment of government performance and trust in most information sources. In the Federal District, there was a negative association between trust levels in the government and worry about pesticides and genetically modified food, but a positive association between trust in NGOs and worry on these hazards. The results point to the need for the implementation of more effective communication strategies by institutions in which the population has low trust levels, such as government and food companies.

Street and drug use experiences among sheltered children and adolescents in the Federal District of Brazil.

PROBLEM: The use of drugs by street children and adolescents is a problem found in most large cities around the world. METHODS: This is a cross-sectional study of street children and adolescents living in shelters in the Federal District, Brazil. An objective questionnaire was applied to 84 individuals from September 2016 to October 2017; 14 of them participated in the qualitative study. FINDINGS: Most participants were adolescents (84.5%) and males (64.3%), with a history of abandonment, domestic violence, and family drug abuse. All spent some time on the street; boys had a higher chance of being behind the school level and using drugs than girls. Over 60% had used drugs in the previous year, mainly alcohol and marijuana. Over 70% understand the health consequences of this behavior, but most have never tried or failed to stop. About 40% consider themselves dependent on drugs. CONCLUSIONS: The results showed that street-life experience, peer pressure, and exposure to drugs within the family had an important impact on respondent's drug use behavior, reinforcing the importance of education programs that focus on the family.

Correction: de Araújo et al. Relationship between Pesticide Standards for Classification of Water Bodies and Ecotoxicity: A Case Study of the Brazilian Directive. Toxics 2022, 10, 767.

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An ultrasensitive LC-MS/MS method for the determination of glyphosate, AMPA and glufosinate in water - analysis of surface and groundwater from a hydrographic basin in the Midwestern region of Brazil.

The intensive use of glyphosate around the world in the last few decades demands constant monitoring of this compound and its metabolite in aquatic compartments. This work aimed to develop a sensitive method for the analysis of glyphosate, AMPA and glufosinate in water by liquid chromatography/tandem mass spectrometry (LC-MS/MS). The method involves analyte concentration by lyophilization (20×) and direct injection on the LC-MS/MS, and was satisfactorily validated at a LOQ of 0.0025 µg L-1. A total of 142 samples of surface and groundwater collected during the 2021/2022 dry and rainy seasons in the Rio Preto Hydrographic Basin were analyzed. All the 52 groundwater samples were positive for glyphosate (up to 1.5868 µg L-1, dry season) and AMPA (up to 0.2751 µg L-1, dry season). A total of 27 of the 90 surface water samples were positive for glyphosate (up to 0.0236 µg L-1), and 31 samples for AMPA (up to 0.0086 µg L-1), of which over 70 % collected during the dry season. Glufosinate was detected in only five samples, four in groundwater (up to 0.0256 µg L-1). The levels found in the samples are much lower than the maximum levels established by the Brazilian legislation for glyphosate and/or AMPA and lower than the most critical toxicological endpoints for aquatic organisms. However, constant monitoring is necessary, demanding sensitive methods to allow the detection of the very low levels of these pesticides in water.

Determination of new psychoactive substances and other drugs in postmortem blood and urine by UHPLC-MS/MS: method validation and analysis of forensic samples.

PURPOSE: This study aimed to validate a modified QuEChERS method followed by ultra-high performance liquid chromatography-tandem mass spectrometry to determine 79 new psychoactive substances (NPS) and other drugs in blood and urine. METHODS: Prescription drugs (n = 23), synthetic cathinones (n = 13), phenethylamines (n = 11); synthetic cannabinoids (n = 8), amphetamines (n = 7) and other psychoactive substances (n = 17) were included in the method. 500 µL of biological fluid was extracted with 2 mL of water/ACN (1:1), 500 mg of anhydrous MgSO4/NaOAc (4:1) added, followed by a supernatant cleanup with 25 mg of primary secondary amine and 75 mg of anhydrous MgSO4. Quantification was done using matrix-matched calibration curves and deuterated internal standards. RESULTS: The method was satisfactorily validated for blood and urine at limit of quantifications ranging from 0.4 to 16 ng/mL, and applied to the analysis of 54 blood (38 postmortem and 16 antemortem) and 16 antemortem urine samples from 68 forensic cases. All urine samples and 59.3% of the blood samples were positive for at least one analyte. Twenty-two analytes were detected in at least one biological sample, including the synthetic cathinones ethylone (222 ng/mL, antemortem blood), eutylone (246 and 446 ng/mL, urine), and N-ethylpentylone (597 and 7.3 ng/mL, postmortem and antemortem blood, respectively). CONCLUSIONS: The validated method was shown to be suitable for the analysis of blood and urine forensic samples and an important tool to collect information on emerging drug threats and understanding the impact of NPS and other drugs in poisoning cases.

Plastic antioxidants: A family of cocaine cutting agents analyzed by short column gas chromatography-mass spectrometry.

Plastic antioxidants (PAOs), which are used in the industry to prevent degradation caused by thermo-mechanical or thermo-oxidative conditions, have been found in cocaine products seized by the Civil Police of the Federal District, Brazil, since 2019. In this study, a 4-meter short column gas chromatography-mass spectrometry (GC-MS) qualitative method was optimized and validated to detect cocaine, PAOs (antioxidant 168, FOS; antioxidant 1076, NOX; and butylated hydroxytoluene, BHT) and 16 other cutting agents in cocaine base and salt. NOX and FOS are high-boiling-point compounds that are not amenable to the standard GC-MS methods. The method uses a 250 °C split mode injection, final temperature of 280 °C, and a total run time of 16.5 min. PAOs were found in 84.2% of the 38 cocaine base samples and in 21.5% of the 65 cocaine salt samples (mainly NOX); 20 samples that did not contain any cocaine also contained PAOs (30% NOX and 25% FOS). Other cutting agents found in the samples included phenacetin, aminopyrine, and lidocaine in cocaine base; lidocaine, tetracaine, and caffeine in cocaine salt. This is the first report of PAOs detected as cocaine cutting agents and shows another important application of the short column GC-MS method in forensic science that can also be applied in other areas involving these compounds.

Relationship between Pesticide Standards for Classification of Water Bodies and Ecotoxicity: A Case Study of the Brazilian Directive.

The objective of this study was to evaluate if the maximum values (MVs) for pesticides in surface freshwater included in CONAMA directive 357/2005 are safe for aquatic biota, comparing them with ecotoxicology data published in the literature. The terms "aquatic toxicity", "chronic" "acute", "LC50", "EC50", "NOEL", "NOEC" and the name of each pesticide were used for searches on the research platforms. Data from 534 tests reported in 37 published articles and three ecotoxicological databases were included in this study; 24% of the tests were carried out with producer organisms, 34% with primary consumers and 42% with secondary consumers. Microcrustaceans of the Daphnia genus and the fishes Pimephales promelas and Oncorhynchus mykiss were the organisms most used. Atrazine, alachlor and metolachlor were the most investigated pesticides. Atrazine and alachlor are approved in Brazil, with atrazine ranking fourth among the most used pesticides in the country. The results indicated that of the 27 pesticides included in the standard directive, 17 have a risk quotient (RQ) higher than the level of concern for at least one ecotoxicological parameter and may not protect the aquatic biota. The insecticide malathion, used in various agricultural crops in Brazil, was the one that presented the highest RQs (3125 and 3,125,000 for freshwaters classified as 1/2 and 3, respectively), related to a LC50 (96 h) of 0.000032 µg/L in Chironomus ramosus. The results indicate that CONAMA directive 357/2005 should be updated in line with the current use of pesticides in the country, and the MVs should be re-evaluated so that they do not represent toxicity for the aquatic biota.

Pesticide residues analysis in passion fruit and its processed products by LC-MS/MS and GC-MS/MS: Method validation, processing factors and dietary risk assessment.

A method for the determination of 80 pesticides (including five metabolites) in passion fruit using ethyl acetate extraction and dispersive solid-phase extraction followed by LC-MS/MS and GC-MS/MS was validated at LOQ of 0.005 or 0.010 mg kg-1 (70 to 120% recovery; RSD ≤ 20%). Fifty-five passion fruit samples were obtained from producers, and 30 samples of frozen pulp and 12 samples of flour purchased. About 27% of the pesticides were detected; at least one in 60% of the peel samples, mainly imidacloprid and carbendazim (max. of 0.274 mg kg-1). Median processing factor was 0.5 for washed peel and 6.5 for dried peel (flour). About 63% of frozen pulp samples were positive, and 4 flour samples contained residues, mainly methamidophos. About 70% of the detected pesticides are not authorized in passion fruit in Brazil. Chronic and acute exposure from the consumption of passion fruit products did not indicate a health concern.

Fatal cases involving new psychoactive substances and trends in analytical techniques.

New psychoactive substances (NPS) are an emerging public health issue and deaths are commonly associated with polydrug abuse. Moreover, the number of new substances available is constantly increasing, causing intoxications in low doses, characteristics that impose to toxicology and forensic laboratories to keep routine methods up to date, with high detectability and constantly acquiring new analytical standards. Likewise, NPS metabolites and respective elimination pathways are usually unknown, making it difficult the detection and confirmation of the drug involved in the fatal case in an analytical routine. A literature search was performed on PubMed, Scopus and Web of Science databases for papers related to chromatographic analyses from fatal cases related to NPS use published from 2016 to 2021. A total of 96 papers were retrieved and reviewed in this study. Opioids, synthetic cathinones, phenethylamines/amphetamines and cannabinoids were the NPS classes most found in the fatal cases. In many cases, multiple compounds were detected in the biological samples, including prescription and other illegal drugs. Liquid chromatography-tandem mass spectrometry, an alternative to overcome the gas chromatography-mass spectrometry limitations for some compounds, was the analytical technique most used in the studies, and high resolution mass spectrometry was often applied to NPS metabolite investigation and structural characterization and identification of unknown compounds. Toxicological screening and quantitation methods need to be continuously updated to include new substances that are emerging on the drug market that can be fatal at very low doses.

Antimicrobial activity and partial chemical structure of acylpolyamines isolated from the venom of the spider Acanthoscurria natalensis.

Background: Acylpolyamines are one of the main non-peptide compounds present in spider venom and represent a promising alternative in the search for new molecules with antimicrobial action. Methods: The venom of Acanthoscurria natalensis spider was fractionated by reverse-phase liquid chromatography (RP-HPLC) and the antimicrobial activity of the fractions was tested using a liquid growth inhibition assay. The main antimicrobial fraction containing acylpolyamines (ApAn) was submitted to two additional chromatographic steps and analyzed by MALDI-TOF. Fractions of interest were accumulated for ultraviolet (UV) spectroscopy and ESI-MS/MS analysis and for minimum inhibitory concentration (MIC) and hemolytic activity determination. Results: Five acylpolyamines were isolated from the venom with molecular masses between 614 Da and 756 Da, being named ApAn728, ApAn614a, ApAn614b, ApAn742 and ApAn756. The analysis of UV absorption profile of each ApAn and the fragmentation pattern obtained by ESI-MS/MS suggested the presence of a tyrosyl unit as chromophore and a terminal polyamine chain consistent with structural units PA43 or PA53. ApAn presented MIC between 128 µM and 256 µM against Escherichia coli and Staphylococcus aureus, without causing hemolysis against mouse erythrocytes. Conclusion: The antimicrobial and non-hemolytic properties of the analyzed ApAn may be relevant for their application as possible therapeutic agents and the identification of an unconventional chromophore for spider acylpolyamines suggests an even greater chemical diversity.

Drugs, pesticides and metabolites in forensic post-mortem blood samples.

Forensic post-mortem toxicological data provide valuable information for the elucidation of cause of death. However, this is still not routine practice in Brazilian laboratories. This study investigated the presence of illicit and prescription drugs, pesticides and metabolites in 111 post-mortem blood samples from cases investigated by the Forensic Medical Institute of the Federal District, Brazil. Quantitative analysis was performed for 14 analytes using a validated programmed temperature vaporisation-large volume injection-gas chromatography-mass spectrometry method, which was also used as screening (qualitative analysis) for an additional 19 substances of forensic interest. At least one analyte was found in 61.2% of the samples, of which 34 were related to homicide, 15 to accidental death and 10 to suicide cases. The victims were 14-72 years old. The benzodiazepines diazepam, midazolam and 7-aminoflunitrazepan were detected in 46% of the positive samples (0.02-1.12 µg/mL; midazolam only qualitative). Cocaine was found in 34% (0.02-4.07 µg/mL), associated with substances commonly used as cocaine adulterants (e.g. caffeine, lidocaine and phenacetin). Three suicide cases involved the illegal rodenticide chumbinho, residues of which were found in the gastric content, and blood samples showed the presence of terbufos (0.03 and 0.04 µg/mL) and carbofuran (27.3 µg/mL). These results are discussed, along with autopsy and crime-scene information.