Local context and environment as risk factors for acute poisoning in animals in northwest Italy

Wildlife ecotoxicology of plant protection products: knowns and unknowns about the impacts of currently used pesticides on terrestrial vertebrate biodiversity

Agricultural practices are a major cause of the current loss of biodiversity. Among postwar agricultural intensification practices, the use of plant protection products (PPPs) might be one of the prominent drivers of the loss of wildlife diversity in agroecosystems. A collective scientific assessment was performed upon the request of the French Ministries responsible for the Environment, for Agriculture and for Research to review the impacts of PPPs on biodiversity and ecosystem services based on the scientific literature. While the effects of legacy banned PPPs on ecosystems and the underlying mechanisms are well documented, the impacts of current use pesticides (CUPs) on biodiversity have rarely been reviewed. Here, we provide an overview of the available knowledge related to the impacts of PPPs, including biopesticides, on terrestrial vertebrates (i.e. herptiles, birds including raptors, bats and small and large mammals). We focused essentially on CUPs and on endpoints at the subindividual, individual, population and community levels, which ultimately linked with effects on biodiversity. We address both direct toxic effects and indirect effects related to ecological processes and review the existing knowledge about wildlife exposure to PPPs. The effects of PPPs on ecological functions and ecosystem services are discussed, as are the aggravating or mitigating factors. Finally, a synthesis of knowns and unknowns is provided, and we identify priorities to fill gaps in knowledge and perspectives for research and wildlife conservation.

First evidence of widespread positivity to anticoagulant rodenticides in grey wolves (Canis lupus)

Second-generation Anticoagulant Rodenticides (ARs) can be critical for carnivores, due to their widespread use and impacts. However, although many studies explored the impacts of ARs on small and mesocarnivores, none assessed the extent to which they could contaminate large carnivores in anthropized landscapes. We filled this gap by exploring spatiotemporal trends in grey wolf (Canis lupus) exposure to ARs in central and northern Italy, by subjecting a large sample of dead wolves (n = 186) to the LC-MS/MS method. Most wolves (n = 115/186, 61.8 %) tested positive for ARs (1 compound, n = 36; 2 compounds, n = 47; 3 compounds, n = 16; 4 or more compounds, n = 16). Bromadiolone, brodifacoum and difenacoum, were the most common compounds, with brodifacoum and bromadiolone being the ARs that co-occurred the most (n = 61). Both the probability of testing positive for multiple ARs and the concentration of brodifacoum, and bromadiolone in the liver, systematically increased in wolves that were found at more anthropized sites. Moreover, wolves became more likely to test positive for ARs through time, particularly after 2020. Our results underline that rodent control, based on ARs, increases the risks of unintentional poisoning of non-target wildlife. However, this risk does not only involve small and mesocarnivores, but also large carnivores at the top of the food chain, such as wolves. Therefore, rodent control is adding one further conservation threat to endangered large carnivores in anthropized landscapes of Europe, whose severity could increase over time and be far higher than previously thought. Large-scale monitoring schemes for ARs in European large carnivores should be devised as soon as possible.

Fast and sensitive method for the diagnosis and follow-up of anticoagulant rodenticides poisoning in animal whole blood

Rodent control strategies are primarily based on the use of anticoagulant rodenticides (ARs), making them widely used worldwide. However, due to their high toxicity and availability, ARs are among the leading causes of animal poisoning in Europe. They are the primary agents involved in intoxication in cats and the second in dogs. Additionally, their long persistence in the body can lead to secondary exposure, particularly in wild predators. The laboratory findings and clinical signs of intoxication can range from increased clotting time (prolonged prothrombin time and activated partial thromboplastin time) to severe bleeding and death. Despite the prevalence and severity of this intoxication, only a few methods are available for the identification and quantification of ARs in animals, and most of them are suitable only for post-mortem diagnosis. In this study, we present the validation of a rapid and sensitive method for the identification and quantification of ARs in animal whole blood, using a small sample volume. The developed LC-MS/MS method demonstrated high accuracy and precision at the limit of quantification (LOQ), as well as at low, medium, and high concentrations. It exhibited higher sensitivity (LOQ 0.1 - 0.3 ng/mL) compared to previously published methods. After validation, the method was successfully applied to real cases of suspected poisoning events, resulting in the identification of several positive samples. The examples presented in this study highlight the utility of this method for diagnosis and follow-up, emphasizing the importance of method sensitivity in order to avoid misclassifying truly positive samples as negative.

Retrospective analysis of forensic toxicology data from 2021 to identify patterns of various forensic cases

PURPOSE

Knowing and analyzing the characteristics and trends of forensic toxicology cases in a certain area is particularly important for a local government to establish an effective prevention and control system. The purpose of this work was to summarize data from forensic toxicology cases received by the Academy of Forensic Sciences (AFS) in 2021.

METHODS

As requested by the police or according to the details of cases, samples were systematically screened or analyzed by various methods. Liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry were used to identify medicinal drugs, drugs of abuse, pesticides, poison gases, etc. RESULTS: AFS received a total of 17,758 cases in 2021, of which 314 cases underwent autopsy. The main cause of death was sudden death, and the manner of death was mainly accident. Among 13,744 drug abuse cases, the number of positive cases was 1721, with a positive rate of 12.5%, and synthetic cannabinoids were the most frequently detected substances. In 3640 traffic cases, 85.3% of drivers were suspected of drunk driving. In 103 poisoning cases, hydrogen sulfide poisoning and pesticide suicide account for a large proportion. In drug-facilitated crimes, zolpidem was the most frequently tested component. In 55 case of dog poisonings, the main poisons were cyanides and succinylcholine, and the main poisoning tools were poisonous baits and poisonous syringe darts.

CONCLUSIONS

This study profiles the toxicological characteristics of forensic toxicological cases conducted at the AFS in 2021 and provides a scientific basis for poisoning cases and drug abuse prevention.

Disgust in animals and the application of disease avoidance to wildlife management and conservation

Disgust is an adaptive system hypothesized to have evolved to reduce the risk of becoming sick. It is associated with behavioural, cognitive and physiological responses tuned to allow animals to avoid and/or get rid of parasites, pathogens and toxins. Little is known about the mechanisms and outcomes of disease avoidance in wild animals. Furthermore, given the escalation of negative human-wildlife interactions, the translation of such knowledge into the design of evolutionarily relevant conservation and wildlife management strategies is becoming urgent. Contemporary methods in animal ecology and related fields, using direct (sensory cues) or indirect (remote sensing technologies and machine learning) means, provide a flexible toolbox for testing and applying disgust at individual and collective levels. In this review/perspective paper, we provide an empirical framework for testing the adaptive function of disgust and its associated disease avoidance behaviours across species, from the least to the most social, in different habitats. We predict various trade-offs to be at play depending on the social system and ecology of the species. We propose five contexts in which disgust-related avoidance behaviours could be applied, including endangered species rehabilitation, invasive species, crop-raiding, urban pests and animal tourism. We highlight some of the perspectives and current challenges of testing disgust in the wild. In particular, we recommend future studies to consider together disease, predation and competition risks. We discuss the ethics associated with disgust experiments in the above contexts. Finally, we promote the creation of a database gathering disease avoidance evidence in animals and its applications.

Pervasive exposure of wild small mammals to legacy and currently used pesticide mixtures in arable landscapes

Knowledge gaps regarding the potential role of pesticides in the loss of agricultural biodiversity worldwide and mixture-related issues hamper proper risk assessment of unintentional impacts of pesticides, rendering essential the monitoring of wildlife exposure to these compounds. Free-ranging mammal exposure to legacy (Banned and Restricted: BRPs) and currently used (CUPs) pesticides was investigated, testing the hypotheses of: (1) a background bioaccumulation for BRPs whereas a "hot-spot" pattern for CUPs, (2) different contamination profiles between carnivores and granivores/omnivores, and (3) the role of non-treated areas as refuges towards exposure to CUPs. Apodemus mice (omnivore) and Crocidura shrews (insectivore) were sampled over two French agricultural landscapes (n = 93). The concentrations of 140 parent chemicals and metabolites were screened in hair samples. A total of 112 compounds were detected, showing small mammal exposure to fungicides, herbicides and insecticides with 32 to 65 residues detected per individual (13-26 BRPs and 18-41 CUPs). Detection frequencies exceeded 75% of individuals for 13 BRPs and 25 CUPs. Concentrations above 10 ng/g were quantified for 7 BRPs and 29 CUPs (in 46% and 72% of individuals, respectively), and above 100 ng/g for 10 CUPs (in 22% of individuals). Contamination (number of compounds or concentrations) was overall higher in shrews than rodents and higher in animals captured in hedgerows and cereal crops than in grasslands, but did not differ significantly between conventional and organic farming. A general, ubiquitous contamination by legacy and current pesticides was shown, raising issues about exposure pathways and impacts on ecosystems. We propose a concept referred to as "biowidening", depicting an increase of compound diversity at higher trophic levels. This work suggests that wildlife exposure to pesticide mixtures is a rule rather than an exception, highlighting the need for consideration of the exposome concept and questioning appropriateness of current risk assessment and mitigation processes.

Acetylcholinesterase (AChE) Reversible Inhibitors: The Role of Oxamyl in the Production of Poisoned Baits

Oxamyl is a highly toxic carbamate molecule with toxicological risk from contamination, used as an insecticide, nematicide, and acaricide on many field crops, vegetables, fruits, and ornamentals. Suspected poisoned animals and baits were collected between January 2018 and August 2021 from Lombardy and Emilia-Romagna regions and analyzed at the chemical toxicology laboratory of the Experimental Zooprophylactic Institute of Lombardy and Emilia-Romagna, located in Brescia. The analyses were carried out by an ion trap GC-MS system in 2467 suspected samples and showed the presence of oxamyl in 67 of these. In this study, we analyzed 47 (out of 67) positive baits: the provinces in which more cases have been recorded are Mantua, Ferrara, and Cremona, which overall had 72% of positivity. The nature of the analyzed samples was mostly corn (55.3%), followed by bird carcasses (19.1%), apples (14.8%), meatballs (2.1%), bread (2.1%), and other (8.5%). The use of oxamyl to produce poisoned baits is constantly increasing, proving that it must be considered as a public health risk for the possible consequences on target and non-target organisms, including humans.

Use of poisoned baits against wildlife. A retrospective 17-year study in the natural environment of Extremadura (Spain)

This study reports the results obtained from toxicological analyses of different types of baits referred to the laboratory of the Toxicology Area (Faculty of Veterinary Medicine, Cáceres, Spain) over a 17-year period (2002-2018). These baits were suspicious materials found in the environment of the region of Extremadura (Western Spain), where such malpractices are a problem to be addressed, as wide livestock farming and hunting activities are combined with a significant wealth of wildlife (especially birds of prey). A total of 246 baits, including 32 commercial chemical products to be used in baits, were analysed. Samples from 183 cases were received and classified according to the material used for their preparation and the toxic substance found. Overall, the most common bait consisted of meat preparations (56.3% of cases) intended to eliminate predators considered 'annoying' for livestock and hunting practices, such as carnivores and scavengers. It should be noted that contact baits (as fenthion-impregnated perches) were also detected (7.6%). Regarding the substances detected, anticholinesterase compounds (organophosphates and carbamates) were the most commonly used substances for the preparation of baits (detected in 85.3% of positive baits). Moreover, 8% of the positive baits presented more than one toxic substance in their composition. Due to the types of toxic compounds and the methods used to prepare the baits, this study shows that the malicious use of highly toxic substances in the environment to kill wildlife is a common and current issue and poses a serious risk to different species.

Bioactive Modified Non-Wovens as a Novel Approach of Plants Protection against Invasive Slugs

Invasive slugs generate significant problems in the area of horticultural and agricultural production. Despite the multitude of methods to reduce the pest population, including preventive, mechanical, agrotechnical, cultivation, biological, and chemical treatments, no effective plant protection strategy has been developed so far. In this paper, a solution based on modified non-woven fabric with bioactive molluscicidal properties using the extract of tansy flower, metaldehyde, and abamectin (Vertigo^® 018 EC) was proposed. All modified mats show significant anti-slug properties in comparison to control, and molluscicidal properties depend on the type of active substance. Non-woven modified with commonly used metaldehyde demonstrated fast action against slugs and presents the highest efficiency. The effectiveness of non-woven mats with Vertigo^® 018 EC is lower than for the mats with metaldehyde but higher than for the mats modified with tansy flower extract. The proposed solution will enable removing and neutralization of molluscicide from the fields, after the efficient pest control, according to circular economy principles. Moreover, it may allow for better control of the molluscicide release to the environment in comparison to widely used pellets, and contribute to the virtual protection of plants against invasive slugs.

Abnormal Prothrombin (PIVKA-II) Expression in Canine Tissues as an Indicator of Anticoagulant Poisoning

PIVKA-II is an aberrant form of vitamin K that has been demonstrated to be increased in human coagulation disorders and in some neoplastic diseases. In veterinary medicine, PIVKA-II levels have been demonstrated to be useful for distinguishing anticoagulant poisoning from other coagulopathies. In forensic pathology, there is the need to distinguish malicious poisoning from other causes of death and, in some cases, identifying poisoned dogs from dogs that died as a result of other coagulative disorders can be challenging. In this study, dogs that suddenly died underwent necropsy, histological examination, and toxicological analysis to establish cause of death. PIVKA-II immunohistochemical expression was evaluated on hepatic and renal tissues, and on neoplastic lesions when present. A total of 61 dogs were analyzed and anticoagulant substances were identified in 16 of the 61. Immunolabelling for PIVKA-II was observed in 27 of 61 cases in the liver and in 24 of 61 cases in the kidneys. Among the poisoned dogs, the PIVKA-II expression was present in the liver in 15 of 16 cases and in the kidneys in 16 of 16. Neoplastic lesions represented mainly by haemangiosarcomas were negative. This study highlights how the immunohistochemical expression of PIVKA-II in hepatic and renal tissues can be useful to identify patients with coagulative disorders due to clinical condition or the ingestion of anticoagulants substances.

Mechanisms of deleterious effects of some pesticide exposure on pigs

The increase in the size of the global population increases the food and energy demand, making the use of pesticides in agricultural and livestock industries unavoidable. Exposure to pesticides can be toxic to the non-target species, such as humans, wildlife, and livestock, in addition to the target organisms. Various chemicals are used in the livestock industry to control harmful organisms, such as insects, weeds, and parasites. Pigs are one of the most important food sources for humans. In addition, pigs can be used as promising models for assessing the risk of absorption of environmental pollutants through the skin and oral exposure since they are physiologically similar to humans. Exposure to numerous environmental pollutants, such as mycotoxins, persistent organic pollutants, and heavy metals, has been reported to adversely affect growth, fertility, and endocrine homeostasis in pigs. Various pesticides have been observed in porcine tissues, blood, urine, and processed foods; however, there is a lack of comprehensive understanding of their effects on porcine health. This review provides a comprehensive description of the characteristics of pesticides that pigs can be exposed to and how their exposure affects porcine reproductive function, intestinal health, and endocrine homeostasis in vivo and in vitro.

Retrospective data analysis of animal poisoning events in Liguria

Confirmed animal poisoning cases were 215/497 (43.2%) from 2009 to 2018.

Anticoagulant rodenticides (79.2%) were the main cause of animal poisoning.

The most affected areas are located along the coast.

Dogs and cats were 40.0% of confirmed animal poisoning.

Intentional poisoning represents a serious risk to domestic and wild animals, and it can be an environmental and human health issue as well . This paper is a retrospective study, which covers a decade, based on animal poisoning cases and poisoned baits that were submitted for diagnostic examinations to the Veterinary Medical Research Institute for Piedmont, Liguria and the Aosta Valley (IZS-PLVA) in Liguria region. All data were collected through a passive surveillance system introduced in Italy by a decree of the Ministry of Health in January 2009.

43.2% of the animal poisoning cases were confirmed by toxicological analysis, whereas toxic agents were detected in 31.1% of the baits. The most affected animal species were dogs and cats, followed by synanthropic birds,. Only 4% of the total poisoning events analysed involved wild animals and cases of livestock poisoning were minimal. An increased number of cases in January, March, April and August was noticed, but no seasonal trend was detected. The most affected areas were the ones with the highest level of urbanization and population density. The major cause of the poisonings and the most common substances detected in the examined baits were anticoagulants whereas cholinesterase inhibitors, organochlorine pesticides and carbamates were detected in a minor number of cases.

This study raises concerns about deliberate animal poisoning in ligurian region and highlights the necessity to fight this phenomenon as it endangers animals, humans and environment.

Fast and simultaneous analysis of carbamate pesticides and anticoagulant rodenticides used in suspected cases of animal poisoning

Carbamate pesticides (CBs) are reported as one of the main causes of intentional or accidental poisoning of animals. Anticoagulant rodenticides (ARs) form the main class of poisons implicated in analyzed poisoned baits. These two groups of pesticide compounds include multiple substances, and thus, the development of a simple and rapid multiclass/multiresidue analytical method for simultaneous identification of both toxicant classes should be a useful strategy for analytical laboratories to reduce analysis time and cost. The present study aimed to elaborate and validate a rapid method to simultaneously determine 11 CBs and 8 ARs in samples of real matrices (bait, stomach content, and liver) from suspected animal poisoning cases. QuEChERS sample treatment and liquid chromatography coupled to hybrid high resolution mass spectrometry were used. The method resulted in good linearity (R2 ≥ 0.98) for all compounds, recovery was between 70% and 120% for CBs and 40-90% for ARs, and precision was ≤ 20% for all compounds. The method was successfully applied to the analysis of 871 real samples originating from suspected cases of animal poisoning, collected from April 2019 to October 2020. Furthermore, full scan dependent data acquisition allowed qualitative retrospective data analysis of an additional 15 compounds outside the scope of the method to be performed; these compounds could potentially be involved in unresolved poisoning cases.

Biases in the Detection of Intentionally Poisoned Animals: Public Health and Conservation Implications from a Field Experiment

Intentional poisoning is a global wildlife problem and an overlooked risk factor for public health. Managing poisoning requires unbiased and high-quality data through wildlife monitoring protocols, which are largely lacking. We herein evaluated the biases associated with current monitoring programmes of wildlife poisoning in Spain. We compared the national poisoning database for the 1990-2015 period with information obtained from a field experiment during which we used camera-traps to detect the species that consumed non-poisoned baits. Our findings suggest that the detection rate of poisoned animals is species-dependent: Several animal groups (e.g., domestic mammalian carnivores and vultures) tended to be over-represented in the poisoning national database, while others (e.g., corvids and small mammals) were underrepresented. As revealed by the GLMM analyses, the probability of a given species being overrepresented was higher for heaviest, aerial, and cryptic species. In conclusion, we found that monitoring poisoned fauna based on heterogeneous sources may produce important biases in detection rates; thus, such information should be used with caution by managers and policy-makers. Our findings may guide to future search efforts aimed to reach a more comprehensive understanding of the intentional wildlife poisoning problem.

Indoor poisoning of companion animals by chemicals

Episodes of indoor exposure to toxic compounds in companion animals are frequent. Toxico-epidemiological data on this matter are fundamental not only to take proper corrective actions but especially because domestic animals represent crucial sentinels for environmental toxicants. In this review we will present an overview on indoor poisoning of companion animals by chemicals in Europe, providing information on trends and emphasizing emerging indoor contaminants. In general, pesticides are the most frequent class of toxicants involved in indoor animal poisoning episodes in Europe. Among them, insecticides (in particular anticholinesterase compounds) and anticoagulant rodenticides are frequently implicated, but molluscicides (i.e. metaldehyde) together with household products have also shown a growing or at least stable trend in the poisoning episodes. Considering the emerging molecules, neonicotinoids (imidacloprid and acetamiprid) and glyphosate formulations have been pointed out, whereas with regard to households, besides the well-known ethylene glycol, attention should be paid to emerging products such as sodium polyacrylate polymeric hydrogels, xylitol, glowsticks and liquid laundry detergent capsules. The environmental contamination by chemical households is a global challenge and bioindicators like pets may be valuable tools to perform a comprehensive monitoring and risk assessment.