Population structure and dynamics of the Mediterranean Pond Turtle Mauremys leprosa (Schweigger, 1812) in contrasted polluted aquatic environments.

Pollution contributes to the degraded state of continental aquatic ecosystems and biodiversity. Some species appear to be tolerant to aquatic pollution, yet little is known about the effects of such pollution on population structure and dynamics. Here, we investigated how wastewater treatment plant (WWTP) effluents of the Cabestany City, in southern France, contribute to the pollution levels of the Fosseille River, and we tested how they could affect population structure and medium-term dynamics of the native freshwater turtle, the Mediterranean Pond Turtle Mauremys leprosa (Schweigger, 1812). Amongst the 68 pesticides surveyed from water samples collected along the river in 2018 and 2021, a total of 16 pesticides were detected, among which eight were found in the upstream section of the river, 15 in the river section located downstream of the WWTP, and 14 in the outfall of the WWTP, exhibiting the contribution of effluents to the river pollution. From 2013 to 2018 and in 2021, capture-mark-recapture protocols were carried out on the freshwater turtle population living in the river. Using robust design and multi-state models, we showed a stable population throughout the study period, with high year-dependent seniority, and a bidirectional transition occurring primarily from the upstream to the downstream river sections of the WWTP. The freshwater turtle population consisted mostly of adults, with a male biased sex ratio detected downstream of the WWTP neither related to sex-dependent survival, recruitment, nor transition, suggesting a male bias in the hatchlings or primary sex ratio. Also, the largest immatures and females were captured downstream of the WWTP, with females having the highest body condition, whereas no such differences were observed in males. This study highlights that population functioning of M. leprosa is driven primarily by effluents induced resources, at least over the medium-term.

Oxidative stress biomarkers in the Mediterranean pond turtle (Mauremys leprosa) reveal contrasted aquatic environments in Southern France.

Increasing anthropogenic activities, like agricultural practices, constitute the main causes of the loss of water quality and disruption of freshwater ecosystems. High concentrations of pesticides, as shown under experimental conditions, can indeed impact freshwater animals. In Southern France, especially in the Pyrénées-Orientales department, because agricultural activities are mainly based on fruit crops and vineyards, glyphosate and AMPA were detected in some watercourses. Thereby we investigated the effects of degraded waters on the physiology of the endemic endangered freshwater species, namely the Mediterranean pond turtle Mauremys leprosa, in contrasted environments along the same rivers on the one hand and between different rivers on the other. We measured the activity and gene expression of two enzymes involved in the oxidative detoxification processes, namely the Catalase and the Superoxide dismutase. We showed significant variations in the Catalase gene expression and activity within turtles of the Fosseille River depending of their location, i.e. upstream or downstream of the wastewater treatment plants (WTP). Because agricultural environments are similar all along this river, they can no be longer considered as the unique source of turtle stress. The processed waters discharged by the WTP, which contribute to watercourses degradation, could therefore considerably impact the biodiversity of the freshwater environments.

Occupational dermatoses: An Asian perspective.

Occupational dermatoses contribute to a significant portion of work-related diseases, especially in Asia, where a major portion of the workforce is in the unorganized sector. This review article is focussed on the frequency and pattern of occupational skin diseases reported across Asian countries and type of allergens implicated in different occupations. The literature was searched systematically using key words 'occupational dermatoses,' 'occupational skin disease' and name of each Asian country. Ninty five full-text articles were considered relevant and evaluated. Some of the dermatoses seen in industrial workers in Asian countries are similar to those in Western countries, including dermatoses due to chromate in construction and electroplating workers, epoxy resin, and chromate in painters, wood dust in workers in the furniture industry, azo dyes in textile workers and formaldehyde and chromates in those working in the leather and dyeing industries, dermatoses in domestic workers, chefs and health-care workers. Dermatoses in workers engaged in agriculture, beedi (tiny cigars) manufacture, agarbatti (incense sticks) production, fish processing, carpet weaving, sanitation and those working in coffee plantations and coal mines appear to be unique to Asian countries. Recognition of clinical patterns and geographic variations in occupational skin diseases will provide an impetus to further strengthen future research in these areas, as well as improving their management.

Risk of pesticide exposure for reptile species in the European Union.

Environmental pollution has an especially high impact on wildlife. This is especially the case in industrialized countries. Although, many species within the European Union benefit from protection by the Habitats Directive, no special consideration is given to possible detrimental effects of pesticides. This is in particular remarkable as negative effects, which may lead to a regional diversity loss, have already been identified in laboratory and mesocosm studies. We conducted a pesticide exposure risk evaluation for all European reptile species with sufficient literature data on the considered biological and ecological aspects and occurrence data within agricultural areas with regular pesticide applications (102 out of 141). By using three evaluation factors - (i) pesticide exposure, (ii) physiology and (iii) life history - a taxon-specific pesticide exposure risk factor (ERF) was created. The results suggest that about half of all evaluated species, and thus at least 1/3 of all European species exhibited a high exposure risk. At the same time, two of them (Mauremys leprosa and Testudo graeca) are globally classified as threatened with extinction in the IUCN Red List of Threatened Species. Variation regarding species occurrence in exposed landscapes between pesticide admission zones within the EU is rather large. This variation is mainly caused by differing land use and species abundances between zones. At the taxonomic level, significant differences in exposure risk can be observed between threatened and non-threatened species, which can be explained by the formers remote distribution areas. Lizards display the highest sensitivity toward pesticides, although no differences in overall ERFs can be observed between taxonomic groups. By identifying species at above-average risk to pesticide exposure, species-based risk evaluations can improve conservation actions for reptiles from cultivated landscapes.

Programa de Formación de Epidemiología de Campo: período 2001-2004

Contiene: estudios de brotes epidémicos, evaluación de un sistema de vigilancia, publicaciones e informes, conferencias científicas.