Should we think about green or white analytical chemistry? Case study: Accelerated sample preparation using an ultrasonic bath for the simultaneous determination of Mn and Fe in beef

Green Analytical Chemistry (GAC) metrics include a variety of criteria, such as the regent amounts and toxicity, energy consumption, generated waste, among others. The analytical greenness metric (AGREE) and its variant for sample preparation (AGREEprep) cover different aspects that contribute to the environmental sustainability of sample preparation. White Analytical Chemistry (WAC) considers not only environmental aspects but also analytical and practical aspects with a holistic vision based on a Red-Green-Blue color model. A case study is presented to assess the green and white profile of a method based on ultrasound-assisted extraction and determination of Mn and Fe in beef using microwave-induced plasma atomic emission spectroscopy (MP AES). The method was validated and resulted simple, fast without external heating using diluted acids. It was concluded that we should think in green sample preparation with the AGREEprep tool, as well as in white holistic assessments (WAC) as both constitute complementary tools.

Arsenic levels in groundwater and its correlation with relevant inorganic parameters in Uruguay: A medical geology perspective

The aim of this work was to perform a groundwater quality monitoring in Uruguay, from the Medical Geology perspective, focusing attention on arsenic levels and its correlations with other relevant inorganic parameters. For this purpose, a total of 46 groundwater samples from private wells, out of the scope of the state-run water utility company, were analyzed. The accuracy of the analytical methods was ensured by using certified reference materials. Arsenic concentration range was 1.72-120.5 μg L^-1, half of the samples being above the limit of 10 μg L^-1 recommended by WHO for drinking water, with the corresponding risks for human health. Pearson correlations were performed, resulting in strong positive correlations for the pairs As/Cl^-, As/F^-, As/Na and As/V. These relationships between arsenic and other inorganic parameters in groundwater should be deeply studied, to prevent long-term health effects.

An overview of environmental arsenic issues and exposure risks in Uruguay

Evidence for low-dose health effects of Arsenic (As) in humans is still controversial and presents a major public health issue in several countries worldwide. It is not clear yet, whether there is a lower safe threshold for arsenic in drinking water among other possible sources such as food, below which, exposures are not harmful. In Uruguay, safe drinking water is supplied to 94% of the population by a state company (OSE) and As levels in workplaces and food are officially regulated. This paper aims to present and discuss the issues regarding arsenic exposure risks to the environment and human population, which are being addressed in a multidisciplinary manner in Uruguay since 2007. An overview is given on both the background and the current situation, presenting reports and research studies conducted on these problems by various academic, state, and private institutions that deal with regulations, surveillance, and health care. Scientific research on geogenic As levels in groundwater indicates As levels above those recommended by the WHO for drinking water (10 μg L^-1) in different Uruguayan aquifers. There is a lack of baseline studies concerning Uruguayan residents that are exposed to As in drinking water over time. Furthermore, there is a need for data on environmental chemical exposure that could be associated with disease or death in the country. In addition, only a few As risk exposure assessment studies in children, adults, and workers using biomarkers in urine are available. Furthermore, this paper presents As levels in a rice growing region and the spatial distribution of groundwater arsenic data compared to a national cancer atlas database as ongoing research advances. Multidisciplinary research projects and local future actions are also described. This contribution constitutes a first attempt to develop a feasible health risk assessment of low-dose arsenic exposure in this Latin-American country.

Total arsenic and inorganic arsenic speciation in groundwater intended for human consumption in Uruguay: Correlation with fluoride, iron, manganese and sulfate

Medical Geology is a growing field in Uruguay and the groundwater quality has been the focus of multiple studies, being As levels one of its main concerns. The aim of this study was the application of analytical methodologies for the assessment of total arsenic and inorganic arsenic species, fluoride, iron, manganese and sulfate in groundwater samples from private wells, used for human consumption, and to evaluate the possible correlations among these parameters. The accuracy of the methods was ensured by using certified reference materials. A total of 48 groundwater samples from Uruguay were analyzed. The concentration ranges found were: tAs (1.72-120.48) μg L^-1, F^- (0.024-1.528) mg L^-1, Fe (0.62-211.38) μg L^-1 and Mn (0.11-8.705) μg L^-1. Almost half of the samples presented tAs concentration levels above those recommended by WHO for drinking water (10 μg L^-1), with the corresponding risks for human health. Results showed higher As(V) levels in the samples, which is in agreement with the oxidant conditions of the wells. Pearson correlations were performed, resulting in strong positive correlations for As/F^-, As(V)/F^- and As(V)/SO₄^2-. As levels in groundwater and its relationship with other inorganic parameters, should be deeply studied to prevent long-term health effects.

Biomonitoring of arsenic in woodworkers exposed to CCA and evaluation of other non-occupational sources in Uruguay

In Uruguay wood-impregnation plants use chromated copper arsenate (CCA) as preservative applying good manufacture practices (GMP). This study aims a retrospective evaluation of toxicologically relevant species levels in CCA exposed woodworker's urine (As-U) and an assessment of the effects of work risk factors and non-occupational sources in As-U of workers from a selected plant. From 2014 to 2016, As-U in 212 urine samples (As-U) of 73 woodworkers from six CCA impregnation plants were determined. In one of these plants, 35 workers were interviewed to obtain individual data of work tasks, lifestyles, diet, habits, etc. that may contribute to their overall exposure to Arsenic. Responses were statistically evaluated. Out of the 212 urine samples from 73 woodworkers, 96% showed lower levels of As-U than those established by health regulations (<35μgL^-1). According to their work tasks 34% of 35 surveyed workers showed high exposure risk to As and 29% moderate exposure risk. Although they have lower levels of As-U owing to their personal protective equipment, As-U significantly correlate to work risk factors. Consumption of bottled water could also contribute to As-U levels as a non-occupational source. These results confirm that efforts of Uruguayan authorities to promote GMP were successful and justify the importance and frequency of As-U systematic biomonitoring for occupational risk assessment. A significant accomplishment of this work is that non-occupational sources of As-like bottled water consumption should also be considered in future studies.