To Örebro University

Hillringsberg, a former sawmill site in Sweden, is severely contaminated with polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This study collected site-specific data to assess the human health risks associated with locally produced food. To evaluate potential exposure, samples of salmon, perch, cow's milk, cattle, and sheep were collected near the site and analyzed for PCDD/Fs. The findings reveal that the most frequently detected congeners in the food samples corresponded with the most abundant congeners in the soil, underscoring the impact of contaminated sites on PCDD/F concentrations in locally produced food. Particularly concerning is the level of PCDD/Fs in sheep meat, which was found to be 11 times higher than the Tolerable Weekly Intake (TWI) for adults and 26 times higher for children. Comparing food samples from the sawmill site to those from the National Swedish Control Programme revealed that all food samples from Hillringsberg exhibited some level of contamination, even though the concentrations of PCDD/Fs remained below the European Maximum Limits (MLs) and Action Limits (ALs). The concentrations and patterns of contaminants in nearly all samples, particularly those from sheep, cattle and perch, were influenced by local contamination from the historical use of pentachlorophenol (PCP) at the old sawmill site. PCA showed that sheep and soil samples from the storage area exhibited strong covariance. Perch and sediment samples from the sawmill pond were also grouped together. These findings highlight the necessity of evaluating food production activities near contaminated sites during the initial stages of site-specific risk assessments. Ensuring food safety in these areas is crucial, and if necessary, relocating grazing lands, fish farms, and similar operations can help mitigate health risks associated with contaminated food.

Brominated flame retardants (BFRs) and organophosphate esters (OPEs) are added to various products to gain specific properties such as reduced flammability and increased flexibility, which has resulted in constant, but usually slow, emission of these compounds to indoor environments. Many BFRs and OPEs are persistent, bioaccumulative and toxic, and have often been detected in indoor dust. This has raised concerns because indoor dust has been identified as one of the major non-dietary exposure pathways for children. In this study, 26 BFRs and OPEs were measured in indoor dust samples collected from 26 preschools in Sweden to identify potential indoor contamination sources and estimate the exposure risk of the detected levels. Among the targeted OPEs, tris(2-butoxyethyl) phosphate (TBOEP) was detected in all the preschools, with a mean concentration of 610 mu g/ g. Among the BFRs, decabromodiphenyl ether (BDE-209) was the predominant compound, with a mean concentration of 130 ng/g, even though it is globally regulated. Triphenyl phosphate (TPHP) was significant higher in preschools built before 2014. Also, 2-ethylhexyl diphenyl phosphate (EHDP) and BDE-209 were significant higher in preschools with sound boards on the walls and without wallpaper, respectively. Furthermore, in three of the participating preschools, an increase in total OPEs was observed between the years 2015 and 2023, possibly due to constant release of the targeted compounds and introduction of new and recycled products. Although the detected indoor dust levels showed a low exposure risk, levels of TBOEP were found to significantly contribute to the chemical burden of children attending the preschools.

Indoor dust contains a complex mixture of chemicals, including endocrine-disrupting chemicals (EDCs), which may pose risks to children's health. As children spend most of their time indoors and have frequent dust contact, their exposure is heightened. This study quantified the endocrine disrupting potential of dust from children's indoor environments in Sweden, and assessed associations with flame retardants and plasticizers in dust, handwipes, and urine.

Fifty dust samples from 18 homes and 11 preschool units were analyzed for estrogen, anti-androgen, and thyroid receptor activities using human osteosarcoma cell-based luciferase reporter assays. Associations were evaluated with 21 legacy and 18 emerging halogenated flame retardants (HFRs) and 11 organophosphate esters (OPEs) in dust and handwipes, as well as nine plasticizers (eight phthalates and di-isononyl cyclohexane 1,2-dicarboxylate (DiNCH)) in dust, and 14 plasticizer metabolites in urine. Samples for biological and chemical analyses were collected from the same designated areas within a limited time frame.

Most dust samples exhibited estrogen receptor agonist (ER) and androgen receptor antagonistic (anti-AR) activity, while thyroid receptor (TR) induction was low. Preschool dust showed significantly higher estrogenic activity than home dust. No seasonal variation was observed. Associations were observed between dust hormonal activities and urinary plasticizer metabolites, as well as HFR and OPE concentrations in dust and handwipes. Relative potency (REP) analyses of 36 HFRs and OPEs revealed notable anti-AR activity for 2,2´,4,4´-tetrabromodiphenyl ether (BDE-47) (REP values 0.85±0.10 (EC25) and 0.93±0.07 (EC50)) and 2,2´,4,4´,6-pentabromo diphenyl ether (BDE-100) (REP values 2.74±0.29 (EC25) and 3.23±0.42 (EC50)). Additionally, BDE-100 showed low ER induction.

Children are exposed to endocrine disrupting chemicals (EDCs) through inhalation and ingestion, as well as through dermal contact in their everyday indoor environments. The dermal loadings of EDCs may contribute significantly to children's total EDC exposure due to dermal absorption as well as hand-to-mouth behaviors. The aim of this study was to measure potential EDCs, specifically halogenated flame retardants (HFRs) and organophosphate esters (OPEs), on children's hands during preschool attendance and to assess possible determinants of exposure in preschool indoor environments in Sweden. For this, 115 handwipe samples were collected in winter and spring from 60 participating children (arithmetic mean age 4.5 years, standard deviation 1.0) and analyzed for 50 compounds. Out of these, 31 compounds were identified in the majority of samples. Levels were generally several orders of magnitude higher for OPEs than HFRs, and 2-ethylhexyl diphenyl phosphate (EHDPP) and tris(2-butoxyethyl) phosphate (TBOEP) were detected in the highest median masses, 61 and 56 ng/wipe, respectively. Of the HFRs, bis(2-ethyl-1-hexyl)-2,3,4,5-tetrabromobenzoate (BEH-TEBP) and 2,2',3,3',4,4',5,5',6,6'-decabromodiphenyl ether (BDE-209) were detected in the highest median masses, 2.8 and 1.8 ng/wipe, respectively. HFR and/or OPE levels were found to be affected by the number of plastic toys, and electrical and electronic devices, season, municipality, as well as building and/or renovation before/after 2004. Yet, the calculated health risks for single compounds were below available reference dose values for exposure through dermal uptake as well as for ingestion using mean hand-to-mouth contact rate. However, assuming a high hand-to-mouth contact rate, at the 95th percentile, the calculated hazard quotient was above 1 for the maximum handwipe mass of TBOEP found in this study, suggesting a risk of negative health effects. Furthermore, considering additive effects from similar compounds, the results of this study indicate potential concern if additional exposure from other routes is as high.

BACKGROUND: Hexavalent chromium (Cr(Ⅵ)) is classified as a group 1 human carcinogen and increases the risk of lung cancer. Non-coding RNAs (ncRNAs) have key regulatory roles in lung cancer, but less is known about their relation to Cr(Ⅵ) exposure.

OBJECTIVES: We aimed to 1) measure the expression of lung cancer-related circulating ncRNAs in exposed workers and controls; 2) assess associations between ncRNAs expression and Cr concentrations in red blood cells (RBC) and urine; and 3) evaluate correlations between the ncRNAs.

METHODS: The study included 111 Cr(VI) exposed workers and 72 controls recruited from the SafeChrom project. Cr concentrations were measured in RBC (biomarker of long-term exposure) and urine (biomarker of short-term exposure) samples. Long ncRNA (lncRNA) and microRNA (miRNA) were extracted from plasma followed by deoxyribonuclease treatment, complementary DNA synthesis, and quantitative real-time polymerase chain reaction using target-specific assays for three lncRNAs (H19, MALAT1, NORAD), and four miRNAs (miR-142-3p, miR-15b-5p, miR-3940-5p, miR-451a).

RESULTS: Expression levels of lncRNAs MALAT1 and NORAD, and all four miRNAs, were significantly lower in Cr(VI) exposed workers compared with controls, and correlated significantly with RBC-Cr concentrations (rS = -0.16 to -0.38). H19 was non-significantly increased in exposed workers but significantly correlated with miR-142-3p (rS = -0.33) and miR-15b-5p (rS = -0.30), and NORAD was significantly positively correlated with all four miRNAs (rS = 0.17 to 0.46). In multivariate regression models adjusting for confounders, expressions of lncRNAs MALAT1 and NORAD and all miRNAs were still significantly lower in the exposed group compared with controls, and the expression decreased with increasing RBC-Cr concentrations.

CONCLUSIONS: Cr(VI) exposure was inversely and in a dose-response manner associated with the expression of circulating non-coding RNA, which suggests ncRNAs as potential biomarkers for Cr(VI)-induced toxicity. Correlations between miRNAs and lncRNAs suggest that they participate in the same lncRNA-miRNA-messenger RNA regulatory axes, which may play important roles in Cr(VI) carcinogenesis.

Objectives: Hexavalent chromium (Cr(VI)) is classified as a human carcinogen. Occupational Cr(VI) exposure can occur during different work processes, but the current exposure to Cr(VI) at Swedish workplaces is unknown.

Methods: This cross-sectional study (SafeChrom) recruited non-smoking men and women from 14 companies with potential Cr(VI) exposure (n = 113) and controls from 6 companies without Cr(VI) exposure (n = 72). Inhalable Cr(VI) was measured by personal air sampling (outside of respiratory protection) in exposed workers. Total Cr was measured in urine (pre-and post-shift, density-adjusted) and red blood cells (RBC) (reflecting Cr(VI)) in exposed workers and controls. The Bayesian tool Expostats was used to assess risk and evaluate occupational exposure limit (OEL) compliance.

Results: The exposed workers performed processing of metal products, steel production, welding, plating, and various chemical processes. The geometric mean concentration of inhalable Cr(VI) in exposed workers was 0.15 mu g/m3 (95% confidence interval: 0.11-0.21). Eight of the 113 exposed workers (7%) exceeded the Swedish OEL of 5 mu g/m3, and the Bayesian analysis estimated the share of OEL exceedances up to 19.6% for stainless steel welders. Median post-shift urinary (0.60 mu g/L, 5th-95th percentile 0.10-3.20) and RBC concentrations (0.73 mu g/ L, 0.51-2.33) of Cr were significantly higher in the exposed group compared with the controls (urinary 0.10 mu g/ L, 0.06-0.56 and RBC 0.53 mu g/L, 0.42-0.72). Inhalable Cr(VI) correlated with urinary Cr (rS = 0.64) and RBC-Cr (rS = 0.53). Workers within steel production showed the highest concentrations of inhalable, urinary and RBC Cr. Workers with inferred non-acceptable local exhaustion ventilation showed significantly higher inhalable Cr(VI), urinary and RBC Cr concentrations compared with those with inferred acceptable ventilation. Furthermore, workers with inferred correct use of respiratory protection were exposed to significantly higher concentrations of Cr(VI) in air and had higher levels of Cr in urine and RBC than those assessed with incorrect or no use. Based on the Swedish job-exposure-matrix, approximately 17 900 workers were estimated to be occupationally exposed to Cr(VI) today.

Conclusions: Our study demonstrates that some workers in Sweden are exposed to high levels of the non-threshold carcinogen Cr(VI). Employers and workers seem aware of Cr(VI) exposure, but more efficient exposure control strategies are required. National strategies aligned with the European strategies are needed in order to eliminate this cause of occupational cancer.

Several plasticizing chemicals induce endocrine disrupting effects in humans, and the indoor environment is suggested to be a source of exposure. As children are particularly vulnerable to the effects from exposure to endocrine disrupting chemicals (EDCs), it is essential to monitor exposure to EDCs such as phthalates and non-phthalate plasticizers in indoor environments intended for use by children. The aim of this study was to assess everyday plasticizer exposure among preschool-aged children in Sweden by measuring urinary plasticizer metabolite concentrations. In addition, it was investigated whether the concentrations would be altered as a result of the children spending part of the day at preschool, in comparison with weekend exposure, when they may spend more time in home environments or engage in various weekend and leisure activities. For this purpose, fourteen metabolites from eight phthalates (di-ethylhexyl phthalate, DEHP; di-n-butyl phthalate, DnBP; di-isobutyl phthalate, DiBP; butyl-benzyl phthalate, BBzP; di-iso-nonyl phthalate, DiNP; di-propylheptyl phthalate, DPHP; di-iso-decyl phthalate, DiDP; and di-ethyl phthalate, DEP) and one non-phthalate plasticizer (di-isononyl cyclohexane 1,2-dicarboxylate, DiNCH) were measured in 206 urine samples collected at four occasions, i.e. twice during the winter and twice during the spring from 54 children (mean 5.1 years, SD 0.94) enrolled at eight preschools in Sweden. A detection frequency (DF) of 99.9% for the 14 metabolites indicates a widespread exposure to plasticizers among children in Sweden. Compared to previous Swedish and international studies performed during approximately the same time period, high urinary concentrations of monobenzyl phthalate (MBzP), a metabolite from the strictly regulated BBzP, were measured in this study (median 17 ng/mL). Overall, high urinary phthalate metabolite concentrations were observed in this study compared to the US CDC-NHANES from the same time period and similar age-group. Compared to European studies, however, similar concentrations were observed for most metabolites and the urinary concentrations from few participating children exceeded the human biomonitoring guidance values (HBM-GV) for children. After days with preschool attendance, lower urinary concentrations of metabolites originating from DEP and phthalates that are strictly regulated within the EU REACH legislation (DEHP, DnBP, and DiBP) and higher concentrations of metabolites originating from DiNP, DPHP, and DiDP, i.e. less or non-regulated phthalates were found compared the urinary concentrations of these metabolites in weekends. This may indicate that factors in the indoor environment itself are important for the extent of the plasticizer exposure. All the analyzed metabolites were measured in lower concentrations in urine collected from children attending preschools built or renovated after the year 2000, while no seasonal differences were observed in this study.

Working as a professional hairdresser involves the daily usage of many different hair treatment products containing chemicals in complex mixtures. Exposure may induce symptoms in the airways and on the skin. In this study, exposure of hairdressers to volatile organic compounds (VOCs), including aldehydes, was measured in the personal breathing zone in the spring of 2017. The study included 30 hairdressers evenly distributed over ten hair salons in the town of Örebro, Sweden. Work tasks and indoor climate were also surveilled. A hazard index (HI) based on chronic reference values for health was calculated to indicate combined exposure risk. In total, 90 VOCs, including nine aldehydes, were identified. Individual exposure expressed as a total concentration of VOCs (TVOCs) were in the range of 50-3600 µg/m3 toluene equivalent (median 460 µg/m3) and the HI was in the range 0.0046-13 (median 0.9). Exposure was more strongly influenced by variability among hairdressers than among salons. The HI indicated an increased risk of non-carcinogenic effects (HI ≥ 1) at four of the 10 hair salons. Individual working procedures, ventilation, volumetric usage of hair treatment products, certain chemicals in products (formaldehyde, isopropanol, and 2,4- and 2,6-toluene diisocyanate), and availability of reference values may have affected estimates of exposure risks. Nevertheless, the HI may be suitable as a screening tool to assess potential exposure risk posed to hairdressers since it considers the complexity of chemical mixtures and the chronic component of VOC exposure occurring in all indoor environments.

This study analysed settled dust samples in Sweden to assess children's combined exposure to 39 organohalogenated flame retardants (HFRs) and 11 organophosphate esters (OPEs) from homes and preschools. >94 % of the targeted compounds were present in dust, indicating widespread use of HFRs and OPEs in Swedish homes and preschools. Dust ingestion was the primary exposure pathway for most analytes, except BDE-209 and DBDPE, where dermal contact was predominant. Children's estimated intakes of ∑emerging HFRs and ∑legacy HFRs from homes were 1-4 times higher than from preschools, highlighting higher exposure risk for HFRs in homes compared to preschools. In a worst-case scenario, intakes of tris(2-butoxyethyl) phosphate (TBOEP) were 6 and 94 times lower than the reference dose for children in Sweden, indicating a potential concern if exposure from other routes like inhalation and diet is as high. The study also found significant positive correlations between dust concentrations of some PBDEs and emerging HFRs and the total number of foam mattresses and beds/m2, the number of foam-containing sofas/m2, and the number of TVs/m2 in the microenvironment, indicating these products as the main source of those compounds. Additionally, younger preschool building ages were found to be linked to higher ΣOPE concentrations in preschool dust, suggesting higher ΣOPE exposure. The comparison with earlier Swedish studies indicates decreasing dust concentrations for some banned and restricted legacy HFRs and OPEs but increasing trends for several emerging HFRs and several unrestricted OPEs. Therefore, the study concludes that emerging HFRs and OPEs are replacing legacy HFRs in products and building materials in homes and preschools, possibly leading to increased exposure of children.

BACKGROUND: Working as a hairdresser involves combined exposure to multiple chemicals in hair treatment products that may induce symptoms in airways and skin.

METHODS: In this cross-sectional study, perceived symptoms among Swedish hairdressers at 10 hair salons were surveyed through a questionnaire. Associations with personal exposure to volatile organic compounds (VOCs), including aldehydes, and their corresponding hazard index (HI), based on the estimated risk for non-cancer health effects, were examined. The prevalence of four out of 11 symptoms was compared to available reference datasets from two other studies of office workers and school staff.

RESULTS: All 11 surveyed symptoms were reported among the hairdressers (n = 38). For the whole study group, the most prevalent symptoms were dripping nose (n = 7) and headache (n = 7), followed by eczema (n = 6), stuffed nose (n = 5), cough (n = 5) and discomfort with strong odors (n = 5). Significant relationships between exposure and symptoms were scarce. The exception was total VOC (TVOC) exposure adjusted to worked years in the profession; a difference was observed for any symptom between hairdressers in the group with 20 + years compared to 0-5 years in the profession (logistic regression, OR 0.03, 95% CI 0.001-0.70). Out of the four symptoms available for comparison, the prevalence of headache and cough was significantly higher in hairdressers than in controls (OR 5.18, 95% CI 1.86-13.43 and OR 4.68, 95% CI 1.17-16.07, respectively).

CONCLUSIONS: Adverse health effects related to occupation was common among the hairdressers, implying a need for exposure control measures in hair salons. Symptoms of headache and cough were more frequently reported by hairdressers than staff in offices and schools. A healthy worker effect among the hairdressers was indicated in the group with 20 + years compared to 0-5 years in the profession. Significant relationships between measured exposure and symptoms were scarce but gave information about advantages and disadvantages of the different exposure measures. The study design could be improved by increasing the size of the study population, using a better match of reference data and increasing the applicability and representability over time of the measured exposure.