in the context of the Fulbright program. Her research has been focused on the toxic effects of pesticides to aquatic and soil organisms, considering both single and mixture exposures to these environmental contaminants widely used in the agricultural practices to increase food production. The applicability of mixture toxicity models as a tool to design environmental friendlier formulations of pesticides has been her general research line. The regulation that controls the use of pesticides is also one of her main interests. The understanding and improvement of the Environmental Risk Assessment schemes that are used to assess the risk that these products can pose to the environmental and human health is imperative and gave rise to the writing of this paper. Joana Luísa Pereira is a researcher at the Department of Biology and the Centre for Environmental and Marine Studies (CESAM) University of Aveiro since her PhD in Biology, awarded in 2008. Her main research lines are within the fields of ecotoxicology and environmental risk assessment, with strong links to limnology (including under regulatory frameworks such as the EU-Water Framework Directive), extreme environments, invasive species and aquatic nuisance management and education for sustainability. She has been investing in the development of new approaches and testing platforms towards the improvement of prospective and retrospective environmental risk assessment routines, always aiming for the increase of environmental realism and/or better prediction capabilities. Pesticides, metal elements and designer chemicals have been the major contaminants focused within this prospective context. She published so far more than 60 SCI papers, collecting more than 800 citations.

Manganese (Mn) is an essential element that participates in several biological processes. Mn serves as a cofactor for several enzymes, such as glutamine synthetase and oxidoreductases, that have an important role in the defense of the organisms against oxidative stress. The diet is the main source of Mn intake for humans, and adequate daily intake levels for this metal change with age. Moreover, in higher amounts, Mn may be toxic, mainly to the brain. Here, we provide an overview of Mn occurrence in food, addressing its bioaccessibility and discussing the dietary standard and recommended intake of Mn consumption. In addition, we review some mechanisms underlying Mn-induced neurotoxicity.

The development of environmentally friendly plant protection products (PPPs), including pesticides, is a challenge nowadays. A commercial herbicide combining terbuthylazine and nicosulfuron as active substances (a.s.) was selected as a model PPP. The suitability of manipulating the ratio between a.s. towards alternative formulations with reduced impacts in a non-target indicator (Lemna minor) was assessed. The efficacy of such eco-friendlier a.s. ratios was then assessed using a target weed, Portulaca oleracea. Single and mixture toxicity testing with L. minor revealed an antagonistic joint action of the a.s., suggesting an environmentally protective effect of the combination compared to single dosing of a.s. The efficacy testing against the target weed of single and combined treatments of the a.s. showed that (i) the a.s. behave antagonistically throughout the whole P. oleracea response surface; (ii) there were no environmentally safe a.s. combinations ensuring target-efficacy; (iii) terbuthylazine alone was effective in controlling P. oleracea with no environmental hazardous potential, dosed at concentrations 10-fold lower than those involved in commercially recommended application doses. Overall, this case-study suggests that modelling tools widely used in the field of environmental risk assessment of PPPs may also have application in PPP design stages for a more efficient meeting of efficacy and environmental friendliness requirements.

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Chemical herbicides have been extensively used in agriculture to control the negative impacts of weeds in crops to improve agricultural yields. Authorized herbicidal active ingredients (AIs) have been combined in...

Chemosensation in nematodes is linked to processes that affect their ability to survive, such as the search for food and the avoidance of toxic substances. Since the 1970s, numerous studies have assessed chemotaxis in the nematode species Caenorhabditis elegans, focusing on a multitude of agents, including bacteria (food), ions, salts, hormones, volatile organic compounds, and, to a lesser extent, metal-contaminated medium/food. The few studies evaluating metal exposure have reported a variety of responses (neutral, attraction, avoidance), which generally appear to be contaminant and/or concentration specific. Differences in experimental designs, however, hinder appropriate comparison of the findings and attainment of firm conclusions. Therefore, we herein propose and describe a detailed protocol for the assessment of the effects of metals on taxis-tofood behavior in C. elegans. Distinct approaches are proposed in two innovative stages of testing to (1) screen metals' effects on taxis-to-food behavior and (2) classify the behavioral response as attraction/avoidance/indifference or preference. Use of such a standard protocol will allow for easy comparison across studies and direct interpretation of results. Findings using this model system can contribute to a deeper understanding of the real risks of metal contamination to nematodes and how such contaminants could impact ecosystems in general, given the key environmental roles that these organisms play. © 2021 Wiley Periodicals LLC.Basic Protocol: Assessing the effects of metal contamination on taxis-to-food behavior in Caenorhabditis elegans Support Protocol 1: Synchronization of C. elegans by hand-picking gravid worms Support Protocol 2: Synchronization of C. elegans by using a bleaching solution