Low levels of potentially toxic elements in workers are associated with self-reported health outcomes.

Occupational exposure to toxic elements can adversely affect health. The current study evaluated blood concentrations of potentially toxic elements (PTE) including As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Sn, and Zn in formal and informal workers. Additionally, the study investigated the associations between blood PTE concentrations and reported health outcomes in the study population. The exposed group included women engaged in informal jewelry welding within their homes in Limeira, São Paulo state, Brazil (n = 36) and men who worked at a steel company in Volta Redonda, Rio de Janeiro state, Brazil (n = 22). The control group comprised residents of the same neighborhoods as the workers but without occupational exposure to chemicals (n = 28 in Limeira; n = 27 in Volta Redonda). Triple Quadrupole Inductively Coupled Plasma Mass Spectrometry (TQ ICP-MS) was used to determine PTE concentrations in blood samples. Glycemia, insulin, and lipid profile tests were performed. All participants completed questionnaires on household risk and reported morbidity. The blood concentrations of Cd, As, and Pb, as well as glycemia, were higher in informal workers than in control subjects. No significant differences were observed between formal workers and control subjects. A robust Poisson regression model, adjusted for variables suggested by a Directed Acyclic Graph, disclosed associations of blood lead and arsenic concentrations with the prevalence of neurological manifestations in Limeira. Blood lead levels > 2.6 µg dL-1 were associated with 2.3 times the prevalence of self-reported neurological manifestations (95 % CI: 1.17-4.58; p = 0.02) than lower blood lead concentrations. Furthermore, a positive association between blood cadmium concentrations and glycemia was observed. Informal occupational exposure to these elements may indicate an increased risk of developing diseases. Monitoring exposure and implementing interventions to reduce PTE exposure in the work environment represent significant steps toward prevention.

Occupational exposure to potentially toxic elements alters gene expression profiles in formal and informal Brazilian workers.

Chemical elements, such as toxic metals, have previously demonstrated their ability to alter gene expression in humans and other species. In this study, microarray analysis was used to compare the gene expression profiles of different occupational exposure populations: a) informal workers who perform soldering of jewelry inside their houses (n = 22) in São Paulo (SP) State; and b) formal workers from a steel company (n = 10) in Rio de Janeiro (RJ) state, Brazil. Control participants were recruited from the same neighborhoods without occupational chemical exposure (n = 19 in SP and n = 8 in RJ). A total of 68 blood samples were collected and RNA was extracted and hybridized using an Agilent microarray platform. Data pre-processing, statistical and pathway analysis were performed using GeneSpring software. Different expression was detected by fold-change analysis resulting in 16 up- and 33 down-regulated genes in informal workers compared to the control group. Pathway analysis revealed genes enriched in MAPK, Toll-like receptor, and NF-kappa B signaling pathways, involved in inflammatory and immune responses. In formal workers, 20 up- and 50 down-regulated genes were found related to antimicrobial peptides, defensins, neutrophil degranulation, Fc-gamma receptor-dependent phagocytosis, and pathways associated with atherosclerosis development, which is one of the main factors involved in the progression of cardiovascular diseases. The gene IFI27 was the only one commonly differentially expressed between informal and formal workers and is known to be associated with various types of cancer. In conclusion, differences in gene expression related to occupational exposure are mainly associated with inflammation and immune response. Previous research has identified a link between inflammation and immune responses and the development of chronic diseases, suggesting that prolonged occupational exposures to potentially toxic elements in Brazilian metal workers could lead to negative health outcomes. Further analysis should be carried out to investigate its direct effects and to validate causal associations.

Is chemical exposure present in informal work associated with Sars-CoV-2 infection?

OBJECTIVE: To compare the incidence of covid-19 symptoms between informal home-based workers and a control group and to assess the association of these cases with blood elements concentrations and other relevant risk factors for Sars-Cov-2 infection. METHODS: Welders chemically exposed to potentially toxic elements (PTEs) (n = 26) and control participants (n = 25) answered questionnaires on adherence to social distancing and signs and symptoms of the disease for five months during the covid-19 pandemic. After follow-up, covid-19 serology tests were performed on a subsample of 12 chemically exposed workers and 20 control participants. Before the pandemic, PTE concentrations in blood (As, Mn, Ni, Cd, Hg, Sb, Sn, Cu, Zn, and Pb) were measured by ICP-MS. RESULTS: The chemically exposed group had higher lead and cadmium levels in blood (p < 0.01). The control group presented lower adherence to social distancing (p = 0.016). Although not significant, welders had a 74% greater chance of having at least one covid-19 symptom compared with control participants, but their adherence to social distancing decreased this chance by 20%. The use of taxis for transportation was a risk factor significantly associated with covid-19 symptoms. CONCLUSION: The lower adherence to social distancing among the control group greatly influences the development of covid-19. The literature lacks data linking exposure to PTEs and Sars-Cov-2 infection and/or severity. In this study, despite chemical exposure, working from home may have protected welders against covid-19, considering that they maintained greater social distancing than control participants.

Is chemical exposure present in informal work associated with Sars-CoV-2 infection?

ABSTRACT OBJECTIVE To compare the incidence of covid-19 symptoms between informal home-based workers and a control group and to assess the association of these cases with blood elements concentrations and other relevant risk factors for Sars-Cov-2 infection. METHODS Welders chemically exposed to potentially toxic elements (PTEs) (n = 26) and control participants (n = 25) answered questionnaires on adherence to social distancing and signs and symptoms of the disease for five months during the covid-19 pandemic. After follow-up, covid-19 serology tests were performed on a subsample of 12 chemically exposed workers and 20 control participants. Before the pandemic, PTE concentrations in blood (As, Mn, Ni, Cd, Hg, Sb, Sn, Cu, Zn, and Pb) were measured by ICP-MS. RESULTS The chemically exposed group had higher lead and cadmium levels in blood (p < 0.01). The control group presented lower adherence to social distancing (p = 0.016). Although not significant, welders had a 74% greater chance of having at least one covid-19 symptom compared with control participants, but their adherence to social distancing decreased this chance by 20%. The use of taxis for transportation was a risk factor significantly associated with covid-19 symptoms. CONCLUSION The lower adherence to social distancing among the control group greatly influences the development of covid-19. The literature lacks data linking exposure to PTEs and Sars-Cov-2 infection and/or severity. In this study, despite chemical exposure, working from home may have protected welders against covid-19, considering that they maintained greater social distancing than control participants.

A Low-Cost Method Shows Potentially Toxic Element Levels in Dust Correlated with Elevated Blood Levels of These Chemicals in Children Exposed to an Informal Home-Based Production Environment.

Dust is recognized as a route of exposure to environmental pollutants. The city of Limeira, Sao Paulo state, Brazil, is a production center for jewelry and fashion jewelry, where part of this jewelry production is home-based, informal, and outsourced. The aim of this study was to evaluate exposure to Potentially Toxic Elements (PTE: Cr, Sn, Mn, Sb, Ni, Cu, Zn, Cd, Pb, and As) in dust among children from households of informal workers using electrostatic dust cloths (EDC). Dust samples were collected in 21 exposed and 23 control families using EDC from surfaces where dust deposits had accumulated for approximately 14 days. In exposed families, dust samples were also collected from welders' workstations. PTE concentrations were then determined using inductively coupled mass spectrometry (ICP-MS). The results raised concerns in relation to Cr, As, and Cd exposure among children within the informal home-based production environment. Blood PTE concentrations in children showed a moderate correlation with levels of Cr (Rho 0.40), Zn (Rho −0.43), and As (Rho 0.40), and a strong correlation with Cd (Rho 0.80) (p < 0.05), detected in dust. In conclusion, analyzing dust collected using EDC proved a potentially low-cost tool for determining PTE in dust. In addition, the results confirmed that informal home-based work poses a risk for children residing in these households. Public policies are needed to assist these families and promote better conditions of occupational health and safety for the whole family.

Study of controlled migration of cadmium and lead into foods from plastic utensils for children.

Lead (Pb) is a highly neurotoxic chemical element known for reducing intelligence quotient (IQ) and promoting antisocial behavior in children and adolescents, while cadmium (Cd) is a carcinogenic bioaccumulative element. Both these metals are included in the priority pollutant list of the United States Environmental Protection Agency and in the WHO List of Chemicals of Major Public Health Concern, where contaminated foods and beverages are the most common pathways of exposure. The objective of this study was to determine total Cd and Pb levels in colored plastic utensils (cups, mugs, bowls, feeding bottles, and plates) for use by children and to measure the specific migration of these elements into beverages and foods. Total contaminant levels were determined using a handheld X-ray fluorescence analyzer. Specific migration tests were conducted using the simulant solutions acetic acid 3% (m/v) and water. Migration levels were determined by ICP-MS. Specific migration tests for Pb were also performed on commercially available samples (cola soft drink, orange juice, vinegar, and milk), with levels determined by graphite-furnace atomic absorption spectrometry (GF-AAS). A total of 674 utensils were analyzed in loco at major commercial centers in Greater São Paulo, of which 87 were purchased for containing Cd and Pb concentrations above permitted limits. Mean concentrations of the metals detected in the purchased utensils were 1110 ppm for Pb and 338 ppm for Cd. For specific migration assays, Pb levels were 187, 13, and 380 times above the permitted limit (0.01 mg.kg -1) for acetic acid, water, and orange juice, respectively. Cd levels were 50 and 2.4 times above the maximum permitted limit (0.005 mg.kg -1) for acetic acid and water, respectively. The districts where the utensils were purchased were grouped according to their social vulnerability index and compared using ANOVA. Pb levels were different between low and medium/high social vulnerability groups (p = 0.006). The findings corroborate the initial hypothesis that these utensils constitute a major source of exposure to PTEs such as Cd and Pb, pointing to the need for stricter regulation and inspection by the Brazilian regulatory agencies.

Additivity of optical emissions applied to neodymium and praseodymium quantification in metallic didymium and (Nd,Pr)-Fe-B alloy samples by low-resolution atomic emission spectrometry: An evaluation of the mathematical approach used to solve spectral interferences.

In this work, the effectiveness of a mathematical approach to solve the spectral interferences involved in the optical emission of two chemical species (neodymium and praseodymium) when using monochromators with low-resolution in atomic spectrometry is evaluated. Although recent technological advances have promoted spectrometers equipped with high-resolution monochromators, which have a great instrumental capability in the separation of nearby lines and consequently avoid spectral interferences, many laboratories still have old spectrometers installed with insufficient resolution to overcome such interferences. In order to evaluate a mathematical approach based on Lambert-Beer's Law, the optical emissions of neodymium and praseodymium were monitored on a low-resolution (200 pm) flame atomic emission spectrometry (F-AES). These two elements were strategically chosen as an application model because they exhibit similar physicochemical properties, joint occurrence in nature and because they are increasingly used in the manufacture of super-magnets, a material increasingly required by the high technology industry. The effectiveness of the mathematical approach was evaluated in three different ways: (i) by recovery of the analytes in synthetic mixtures containing known quantities of the species; (ii) by spike and recovery trials on a representative blend of dissolved samples and (iii) by comparing the results obtained with another analytical method: Inductively coupled plasma optical emission spectrometry (ICP-OES) with a higher spectral resolution. The results indicate the effectiveness of this simple mathematical approach, allow the "survival" of instruments equipped with low-resolution monochromators and demonstrate the applicability of this approach to spectral correction. In addition, this work contributes an analytical method for the quantification of neodymium and praseodymium in metallic alloy samples involved in the production of super-magnets, aiding in the strict quality control of these materials.

Hairdressers are exposed to high concentrations of formaldehyde during the hair straightening procedure.

The fact that hairdressers are exposed to toxic substances through the handling of creams and smoothing products prompted this study whose aim was to quantify the occupational exposure of hairdressers to formaldehyde by comparing the results of exposure for different types of beauty salon. The study population consisted of 23 beauty salons located in the city of Bauru, São Paulo state, Brazil. The samples were collected by inhaled air tests during the most critical 15-min period of the hair straightening procedure and during the 8-h work shift. The concentrations of formaldehyde contained in the formulations of these products were also evaluated and compared with exposure levels. The results were evaluated according to the exposure limits prescribed in Brazilian (NR15) and North American (US OSHA and US NIOSH) standards. The analysis of the smoothing products showed concentrations of formaldehyde of between 3 and 11% in their compositions, i.e., up to 54 times above the 0.2% limit allowed by the National Agency of Sanitary Surveillance (ANVISA). The present study showed that hairdressers are chronically exposed to high concentrations of formaldehyde in the workplace and these exposures are mainly associated with the work process, where many variables of this process influence the intensity of exposure.

Brazilian preschool children attending day care centers show an inadequate micronutrient intake through 24-h duplicate diet.

Inadequate micronutrient intake in childhood harms growth and development, and it is related to increased rates of morbidity and mortality. The aim of this study is to evaluate the dietary intake and prevalence of inadequate micronutrient intake in preschool children (1-4 years old) attending two-day care centers. To assess children's dietary micronutrient intake, 24-h duplicate diets (n = 64) were collected for one week-day, including everything the children ate and drank both at home and in kindergarten. Anthropometric measurements were carried out to evaluate the children's nutritional status. The micronutrients copper, iron, calcium, magnesium, selenium, zinc, potassium, sodium, and manganese were determined by inductively coupled plasma mass spectrometry or graphite furnace atomic absorption spectrometry. Calcium and selenium were found with high inadequate intake rates: 50% and 42%, respectively, for children aged 1-3 years old, and 93% and 90% for children aged 4 years. Potassium was consumed in very low amounts, 13% and 5% of children aged 1-3 and 4 years old, respectively, achieved the adequate intake for the nutrient. Sodium intakes were excessive: 23% of the 1-3-year old and 42% of the 4-year-old children, respectively, had an intake higher than the tolerable upper levels. Regarding the nutritional status, overweight and obesity prevalence was 17%. Therefore, considering the damaging health effects for children of micronutrient deficiency and overweight and obesity status, it is necessary that government authorities be aware and update public policies and educational programs in order to promote healthy eating habits in early childhood.

Lead exposure from households and school settings: influence of diet on blood lead levels.

Lead is known as a potent toxicant to human health, particularly for children while their central nervous system is developing. The aim of this study was to investigate the associations between blood lead levels (BLLs) and lead exposure in the children's diet, home, and school environments. A cross-sectional study was conducted with 153 children aged 1-4 years, in four day care centers (DCCs), where a high prevalence of lead exposure was previously found. Lead determination by graphite furnace atomic absorption spectrometry (GF-AAS) was performed for venous blood, drinking water collected in the DCCs, and the 24-h diet (n = 64). Environmental screenings were conducted to evaluate lead concentrations in the tableware, buildings, and playground items in all DCCs and children's homes (n = 18) by using a field-portable X-ray fluorescence analyzer (FP-XRF). The BLL mean was 2.71 µg dL-1. Means for 24-h lead concentrations in the diet were 1.61 and 2.24 µg kg-1 of body weight (BW) in two DCCs. Lead concentrations in the water supply were lower than 2 µg L-1. More than 11% of the DCCs' environmental analyses presented lead concentrations higher than or equal to 1 mg cm-2, as defined by the USEPA. The diet was not found to be a risk factor for lead exposure, but households and DCC settings raised concern. Children's exposure to lead in DCC environments, where they spend the most part of their weekdays, appeared to be relevant. Graphical abstract ᅟ.

The environmental impact of informal and home productive arrangement in the jewelry and fashion jewelry chain on sanitary sewer system.

The outsourcing informal home practices adopted in jewelry and fashion jewelry chain can cause toxic substance elimination in the effluents and raise a concern for its environmental impact. This study evaluates if this informal work alters the concentration of potentially toxic elements (PTEs: As, Cd, Cr total and Cr-VI, Cu, Hg, Ni, Pb, Sn, and Zn) in the sewage network. The sanitary sewage samples (n = 540) were collected in 15 manholes during two campaigns in three different areas of Limeira-SP, Brazil (industrial area, with informal work and without known industrial/informal activity). The sewage sludge (n = 12), raw (n = 12), and treated sewage (n = 12) were collected in two wastewater treatment plants (WWT: AS and TATU) operating with different treatment process. The PTE determination was performed by ICP-OES, direct mercury analysis, and UV-Vis spectroscopy. Cr-VI, Cu, Ni, and Zn were the only elements above the quantification limit. Four samples exceeded Cu or Zn values permitted to be discharged into sewage system; however, the concentration average was lower than that established by Brazilian legislation. A difference was found between values above and below the 75th percentile for campaign and total organic carbon values (p < 0.015). The AS-treated sewage presented low concentrations of Cu (p < 0.05), Zn (p = 0.02), and Ni (p = 0.01) compared to treated sewage from TATU. In the sludge samples, the Cu means exceeded the limits of the Brazilian legislation (1500 mg kg-1) and the Zn results were very close to the limits (2800 mg kg-1). The heterogeneity of the results can indicate the sporadic nature of the PTE's sanitary disposal. PTEs used in jewelry and fashion jewelry chain may precipitate on the sludge, where presented high concentrations of Cu and Zn which require controlled destination.

Can in vivo surface dental enamelmicrobiopsies be used to measure remote lead exposure?

Measuring lead in the surface dental enamel (SDE) using biopsies is a rapid, safe, and painless procedure. The dental enamel lead levels (DELLs) decrease from the outermost superficial layer to the inner layer of dental enamel, which becomes crucial for the biopsy depth (BD) measurement. However, whether the origin of lead found in SDE is fully endogenous is not yet established. There is also controversy about the biopsy protocol. The aims of this study were to investigate if DELLs are altered by extrinsic contamination (A) and to evaluate the real geometric figure formed by the erosion provoked by biopsy procedure and the respective BD in SDE (B). To accomplish the aim A, lead from 90 bovine incisor crowns lead was determined by graphite furnace atomic absorption spectrometer as a function of exposure time and lead concentration. Two biopsies were performed in each tooth, before and after lead exposure. Six 15-tooth groups differed by exposure time (1 or 30 min) and lead concentrations (A. 0 mg/L-placebo, B. 0.01 mg/L-standard for drinking water, or C. 0.06 mg/L-concentration found in contaminated groundwater). Phosphorus was determined by an inductively coupled plasm optical emission spectrometer to quantify the enamel removed. To compare intakes/losses of lead in SDE among the groups, values of DELL differences between before and after lead exposure were compared by ANOVA (p < 0.05). To attain the objective B, one extracted human permanent tooth was studied by confocal Raman microscopy. Lead measurements and the surface profile were determined. There was no difference in DELL among the groups (p = 0.964). The biopsy bottom surface area, analyzed by microscopy, showed an irregular area, with regions of peaks and valleys, where areas with depth ranging from 0.2 (peaks) to 1.8 µm (valleys) (± 0.1 µm) could be found. BD carried out in vivo is commonly calculated using the cylinder height formula. The real BD was shown to be very similar to already published data. In conclusion, the SDE of erupted teeth does not seem to be susceptible to environmental lead intake, being thus reliable to measure remote exposures to lead.

Ultrasmall cationic superparamagnetic iron oxide nanoparticles as nontoxic and efficient MRI contrast agent and magnetic-targeting tool.

Fully dispersible, cationic ultrasmall (7 nm diameter) superparamagnetic iron oxide nanoparticles, exhibiting high relaxivity (178 mM(-1)s(-1) in 0.47 T) and no acute or subchronic toxicity in Wistar rats, were studied and their suitability as contrast agents for magnetic resonance imaging and material for development of new diagnostic and treatment tools demonstrated. After intravenous injection (10 mg/kg body weight), they circulated throughout the vascular system causing no microhemorrhage or thrombus, neither inflammatory processes at the mesentery vascular bed and hepatic sinusoids (leukocyte rolling, adhesion, or migration as evaluated by intravital microscopy), but having been spontaneously concentrated in the liver, spleen, and kidneys, they caused strong negative contrast. The nanoparticles are cleared from kidneys and bladder in few days, whereas the complete elimination from liver and spleen occurred only after 4 weeks. Ex vivo studies demonstrated that cationic ultrasmall superparamagnetic iron oxide nanoparticles caused no effects on hepatic and renal enzymes dosage as well as on leukocyte count. In addition, they were readily concentrated in rat thigh by a magnet showing its potential as magnetically targeted carriers of therapeutic and diagnostic agents. Summarizing, cationic ultrasmall superparamagnetic iron oxide nanoparticles are nontoxic and efficient magnetic resonance imaging contrast agents useful as platform for the development of new materials for application in theranostics.