RESUMO
Despite discourse advocating pesticide reduction, there has been an exponential increase in pesticide use worldwide in the agricultural sector over the last 30 years. Glyphosate-Based Herbicides (GBHs) are the most widely used pesticides on the planet as well as in Canada, where a total of almost 470 million kilograms of declared "active" ingredient glyphosate was sold between 2007 and 2018. GBHs accounted for 58% of pesticides used in the agriculture sector in Canada in 2017. While the independent scientific literature on the harmful health and environmental impacts of pesticides such as GBHs is overwhelming, Canada has only banned 32 "active" pesticide ingredients out of 531 banned in 168 countries, and reapproved GBHs in 2017 until 2032. This article, based on interdisciplinary and intersectoral research, will analyze how as a result of the scientific and regulatory captures of relevant Canadian agencies by the pesticide industry, the Canadian regulation and scientific assessment of pesticides are deficient and lagging behind other countries, using the GBH case as a basis for analysis. It will show how, by embracing industry narratives and biased evidence, by being receptive to industry demands, and by opaque decision making and lack of transparency, Health Canada's Pest Management Regulatory Agency (PMRA) promotes commercial interests over the imperatives of public health and environmental protection.
RESUMO
Pregnancy is a complex process requiring tremendous physiological changes in the mother in order to fulfill the needs of the growing fetus, and to give birth, expel the placenta and nurse the newborn. These physiological modifications are accompanied with psychological changes, as well as with variations in habits and behaviors. As a result, this period of life is considered as a sensitive window as impaired functional and physiological changes in the mother can have short- and long-term impacts on her health. In addition, dysregulation of the placenta and of mechanisms governing placentation have been linked to chronic diseases later-on in life for the fetus, in a concept known as the Developmental Origin of Health and Diseases (DOHaD). This concept stipulates that any change in the environment during the pre-conception and perinatal (in utero life and neonatal) period to puberty, can be "imprinted" in the organism, thereby impacting the health and risk of chronic diseases later in life. Pregnancy is a succession of events that is regulated, in large part, by hormones and growth factors. Therefore, small changes in hormonal balance can have important effects on both the mother and the developing fetus. An increasing number of studies demonstrate that exposure to endocrine disrupting compounds (EDCs) affect both the mother and the fetus giving rise to growing concerns surrounding these exposures. This review will give an overview of changes that happen during pregnancy with respect to the mother, the placenta, and the fetus, and of the current literature regarding the effects of EDCs during this specific sensitive window of exposure.
Assuntos
Mães , Maturidade Sexual , Feminino , Feto , Humanos , Recém-Nascido , Placenta/metabolismo , Placentação , GravidezRESUMO
Dechlorane Plus (DP) is a chlorinated flame retardant used mainly in electrical wire and cable coating, computer connectors, and plastic roofing materials. Concentrations of DP (syn and anti isomers) are increasingly being reported in aquatic ecosystems worldwide. However, there is exceedingly little information on the exposure-related toxicity of DP in aquatic organisms, especially in bivalves. The objective of this study was to investigate the in vivo and in vitro effects of DP exposure on histopathology, lipid peroxidation (LPO) levels, cyclooxygenase (COX) activity, phagocytosis capacity and efficiency, and DNA strand breakage in the blue mussel (Mytilus edulis) following a 29days exposure (0.001, 0.01, 0.1 and 1.0µg DP/L). Blue mussels accumulated DP in muscle and digestive gland in a dose-dependent manner. LPO levels in gills were found to increase by 82% and 67% at the 0.01 and 1.0µg DP/L doses, respectively, while COX activity in gills decreased by 44% at the 1µg/L dose. No histopathological lesion was found in gonads following DP exposure. Moreover, no change in hemocyte DNA strand breakage, phagocytosis rate, and viability was observed following DP exposure. Present study showed that toxicity of DP may occur primarily via oxidative stress in the blue mussel and potentially other bivalves, and that gills represent the most responsive tissue to this exposure.
Assuntos
Retardadores de Chama/toxicidade , Hidrocarbonetos Clorados/toxicidade , Mytilus edulis/efeitos dos fármacos , Compostos Policíclicos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Dano ao DNA , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Músculos/efeitos dos fármacos , Músculos/metabolismo , Mytilus edulis/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Prostaglandina-Endoperóxido Sintases/metabolismoRESUMO
Sexing methods of blue mussels are mostly based on the presence or absence of gametes, and do not take into account reproductive cycle stages. Exposure effects can be affected by the sex of mussels, thus the aim of this study is to determine an efficient sex determination protocol taking into account the reproductive cycle stage. Eight mussel sexing methods were compared. This study demonstrates that the first step in discerning sex in blue mussels should be assessing the reproductive stage, which can be done by mantle histology. During gametogenesis, histology allows the differentiation of males from females by the observation of gametes. However, when mussels are in sexual rest, the only method that should be used is the sex-specific gene method.
Assuntos
Monitoramento Ambiental/métodos , Mytilus edulis/fisiologia , Animais , Feminino , Células Germinativas , Gônadas , Masculino , ReproduçãoRESUMO
In recent decades there has been an increasing recognition of the need to account for sex and gender in biology and medicine, in order to develop a more comprehensive understanding of biological phenomena and to address gaps in medical knowledge that have arisen due to a generally masculine bias in research. We have noted that as basic experimental biomedical researchers, we face unique challenges to the incorporation of sex and gender in our work, and that these have remained largely unarticulated, misunderstood, and unaddressed in the literature. Here, we describe some of the specific challenges to the incorporation of sex and gender considerations in research involving cell cultures and laboratory animals. In our view, the mainstreaming of sex and gender considerations in basic biomedical research depends on an approach that will allow scientists to address these issues in ways that do not undermine our ability to pursue our fundamental scientific interests. To that end, we suggest a number of strategies that allow basic experimental researchers to feasibly and meaningfully take sex and gender into account in their work.