Water, soap, and hand-disinfectant exposure during the COVID-19 pandemic and self-reported hand eczema in frontline workers: A cross-sectional study.

BACKGROUND: During the COVID-19 pandemic, increased hand hygiene practices were implemented. Impaired skin health on the hands among healthcare workers has been reported previously. Knowledge of how worker in other occupations have been affected is scarce. OBJECTIVES: To investigate self-reported hand water-, and soap exposure and use of hand disinfectants, and hand eczema (HE) in frontline workers outside the hospital setting and in IT personnel during the COVID-19 pandemic. METHODS: In this cross-sectional study, a questionnaire was sent out between 1 March and 30 April in 2021, to 6060 randomly selected individuals representing six occupational groups. RESULTS: A significant increase in water exposure and hand disinfectant use was shown: Relative position (RP) 19; 95% confidence interval (CI) 0.17-0.21 and RP = 0.38: 95% CI 0.36-0.41, respectively. Newly debuted HE was reported by 7.4% of the population, more frequently among frontline workers (8.6%) compared to IT personnel (4.9%). CONCLUSIONS: Water and soap exposure and use of hand disinfectants increased during COVID-19 pandemic, which may increase the risk of hand eczema. This highlights the importance of communication and implementation of preventive measures to protect the skin barrier also in occupations other than healthcare workers.

Inflammation-related proteins in blood after dermal exposure to some common chemicals depend on the skin barrier gene filaggrin - a human experimental study.

Filaggrin (FLG), a skin barrier protein, is associated with higher dermal uptake of some chemicals in carriers of loss-of-function (null) mutations. This study investigates FLG mutations and systemic effects following dermal exposure to chemicals. Individuals (n = 23 FLG null, n = 31 FLG wt) were simultaneously exposed to pyrimethanil, pyrene, oxybenzone, and nickel ions for 4 h. Pre- and post-exposure, 25-hydroxyvitamin D3 (25(OH)D3, LC-MS/MS) and 92 inflammation-related proteins (proximity-extension assay) were measured. FLG null carriers exhibited significantly higher 25(OH)D3 concentrations than wt carriers, both pre- and post-exposure. Eleven proteins differed in abundance post- vs pre-exposure among FLG null carriers, and 22 proteins among wt carriers (three proteins overlapped). Twelve proteins showed median differences (post- vs pre-exposure) between FLG null and wt carriers. Overall, FLG null carriers showed an increase, while FLG wt carriers showed a decrease in inflammation-related proteins. These findings suggest FLG-dependent differences in susceptibility to systemic effects following simultaneous dermal chemical exposure.

Safety data sheets as an information pathway on hazards of occupationally used cleaning agents.

To investigate consistency and accessibility of asthma and skin allergy hazard information in safety data sheets (SDSs) for cleaning agents on the Swedish market, we compiled a database of 504 SDSs and 351 therein declared ingredients. Labelling of products was compared to that of ingredients according to harmonised classification. For each ingredient, also notified classification and three additional sources on sensitising properties were compared. Product labelling most frequently indicated corrosion and irritation hazards. Only 3% of products were labelled as skin sensitisers and none as asthmagens. According to harmonised classification, 9% of products contained skin sensitisers, using other information sources increased the number to 46%. While 2% of products contained respiratory sensitisers according to harmonised classification, the number increased to 17% when using other information sources. Furthermore, sensitisers were declared across several sections of the SDSs, hampering easy access of such information. In conclusion, there are inconsistencies in hazard identification of cleaning agents and their ingredients. Hence, SDSs may not altogether fulfil its hazard information role. Improved criteria for identifying sensitisers and respiratory irritants are warranted. Additionally, we argue that all ingredients should be listed in section 3 regardless of concentration, to facilitate access of information about sensitising properties.

Cobalt nanoparticles cause allergic contact dermatitis in humans.

BACKGROUND: Cobalt (Co) causes allergic contact dermatitis (ACD) and the emerging use of Co nanoparticles (CoNPs) warrants gaining further insight into its potential to elicit ACD in sensitized individuals. OBJECTIVES: The aims of the study were to clarify to what extent CoNPs may elicit ACD responses in participants with Co contact allergy, and to evaluate whether the nanoparticles cause a distinct immune response compared with cobalt chloride (CoCl2) in the skin reactions. METHODS: Fourteen individuals with Co contact allergy were exposed to CoNPs, CoCl2, a Co-containing hard-metal disc (positive control), and an empty test chamber (negative control) by patch testing. Allergic responses were evaluated clinically by a dermatologist at Days 2, 4 and 7. At Day 2, patch-test chambers were removed, and remaining test-substance and skin-wipe samples were collected for inductive-coupled plasma mass spectrometry (ICP-MS) analysis. Additionally, skin biopsies were taken from patch-test reactions at Day 4 for quantitative real-time polymerase chain reaction analysis, histopathology and ICP-MS analysis of Co skin penetration. RESULTS: Patch testing with CoNPs elicited allergic reactions in Co-sensitized individuals. At all timepoints, clinical assessment revealed significantly lower frequencies of positive patch-test reactions to CoNPs compared with CoCl2 or to the positive control. CoNPs elicited comparable immune responses to CoCl2. Chemical analysis of Co residues in patch-test filters, and on skin, shows lower doses for CoNPs compared with CoCl2. CONCLUSIONS: CoNPs potently elicit immune responses in Co-sensitized individuals. Even though patch testing with CoNPs resulted in a lower skin dose than CoCl2, identical immunological profiles were present. Further research is needed to identify the potential harm of CoNPs to human health.

Nickel penetration into stratum corneum in FLG null carriers-A human experimental study.

BACKGROUND: The filaggrin gene (FLG) plays a role in skin diseases, with the skin barrier function being impaired in FLG null carriers. The role of FLG status in relation to nickel penetration into the skin remains unclear. OBJECTIVES: To elucidate the association between FLG status and nickel penetration into stratum corneum (SC) in individuals without self-reported history of nickel allergy. METHODS: Forty participants (23 FLG wt and 17 FLG null) were exposed to a nickel solution (80 µg/cm2 ) which was applied onto 2 × 2 cm on their left forearm. After 4 h, the area was tape-stripped with 10 consecutive tapes. Nickel in each tape was quantified using inductively coupled plasma mass spectrometry. RESULTS: The average recovered nickel dose was 35%-48%. A tendency towards lower recovery was seen in FLG null carriers compared to FLG wt carriers, and lower recovery in those with history of skin and/or respiratory symptoms compared to those without such history. This was however not statistically significant. CONCLUSION: FLG null carriers had less nickel recovered by tape strips compared with FLG wt carriers and, compared with individuals without a history of skin and/or respiratory symptoms, indicating higher nickel penetration into SC for FLG null carriers, but further studies are needed.

An Overview of Cleaning Agents' Health Hazards and Occupational Injuries and Diseases Attributed to Them in Sweden.

Using data from the Swedish Products Register, hosted by the Swedish Chemicals Agency (KemI), national occupational injury and disease statistics, and call records from the Swedish Poisons Information Centre (PIC) we characterize health hazards of marketed cleaning products and recorded injuries, disease, and incidents linked to cleaning or disinfection agents. The results show that cleaning agents pose many kinds of health hazards, although corrosion and irritation hazards dominate, in particular for the eyes (54% of all included products). Few products were recognized as inhalation hazards. The nature of the health hazards is reflected in the occupational disease and injury statistics and PIC records for eyes and skin but not for the respiratory tract. Among occupational disease cases attributed to cleaning or disinfection agents, 61% concern skin and 26% the respiratory tract. Among occupational injury cases 64% concern chemical burns. However, only a small part (<0.5%) of all reported diseases and injuries were explicitly attributed to cleaning or disinfection agents. On average, there were 11 cases of disease attributed to cleaning or disinfection agents per million workers and year. For occupational injuries the corresponding number was 8. The data concern a broad range of sectors and occupations, but notable sectors were healthcare, accommodation and food service, and manufacturing. Women were more likely to suffer from disease, men and women equally likely to suffer from injury. PIC cases were evenly distributed between men and women, but the clear risk cases more frequently involved men. Occupational diseases increased many-fold in 2020 while injuries decreased, which could be due to COVID-19 changing use patterns of cleaning and disinfection agents at work. We conclude that cleaning agents pose a variety of risks to a large part of the workforce, although particular attention for preventive efforts may need to be directed to the healthcare, accommodation and food service, and manufacturing sectors.

Filaggrin Polymorphisms and the Uptake of Chemicals through the Skin-A Human Experimental Study.

BACKGROUND: The filaggrin protein is important for skin barrier structure and function. Loss-of-function (null) mutations in the filaggrin gene FLG may increase dermal absorption of chemicals. OBJECTIVE: The objective of the study was to clarify if dermal absorption of chemicals differs depending on FLG genotype. METHOD: We performed a quantitative real-time polymerase chain reaction (qPCR)-based genetic screen for loss-of-function mutations (FLG null) in 432 volunteers from the general population in southern Sweden and identified 28 FLG null carriers. In a dermal exposure experiment, we exposed 23 FLG null and 31 wild-type (wt) carriers to three organic compounds common in the environment: the polycyclic aromatic hydrocarbon pyrene, the pesticide pyrimethanil, and the ultraviolet-light absorber oxybenzone. We then used liquid-chromatography mass-spectrometry to measure the concentrations of these chemicals or their metabolites in the subjects' urine over 48 h following exposure. Furthermore, we used long-range PCR to measure FLG repeat copy number variants (CNV), and we performed population toxicokinetic analysis. RESULTS: Lag times for the uptake and dermal absorption rate of the chemicals differed significantly between FLG null and wt carriers with low (20-22 repeats) and high FLG CNV (23-24 repeats). We found a dose-dependent effect on chemical absorption with increasing lag times by increasing CNV for both pyrimethanil and pyrene, and decreasing area under the urinary excretion rate curve (AUC(0-40h)) with increasing CNV for pyrimethanil. FLG null carriers excreted 18% and 110% more metabolite (estimated by AUC(0-40h)) for pyrimethanil than wt carriers with low and high CNV, respectively. CONCLUSION: We conclude that FLG genotype influences the dermal absorption of some common chemicals. Overall, FLG null carriers were the most susceptible, with the shortest lag time and highest rate constants for skin absorption, and higher fractions of the applied dose excreted. Furthermore, our results indicate that low FLG CNV resulted in increased dermal absorption of chemicals. https://doi.org/10.1289/EHP7310.

A novel approach to monitor skin permeation of metals in vitro.

How metals permeate skin is poorly understood. Risk assessments tend to take default approaches to account for the dermal route, often using numbers of questionable relevance. Moreover, simultaneous exposure to multiple metals may affect the permeation of individual metals. To investigate this, we developed an experimental setup where receptor medium circulates directly from a conventional diffusion cell for in vitro skin absorption into an inductively coupled plasma mass spectrometer (ICP-MS), enabling continuous measurement of metal concentration. Full-thickness piglet skin was used as diffusion barrier, artificial sweat as donor medium and phosphate buffered saline as receptor medium. Percutaneous absorption from donor medium containing 2 mmol/L of nickel, cobalt, or chromium or all three combined was monitored for 2 h. Metals retained in skin were quantified post-exposure. Percutaneous absorption of nickel was faster in single than in combined exposure; for cobalt and chromium no such difference was apparent. Similar amounts of the three metals were retained in skin after single exposure, and retention was consistently higher for each metal after combined exposure. This study provides proof-of-concept for a method that reliably detects concentration changes in physiologically relevant medium. It may shed light on skin absorption and permeation kinetics of metals and risks associated with metal exposure.

A Case Study of Brass Foundry Workers' Estimated Lead (Pb) Body Burden from Different Exposure Routes.

OBJECTIVES: The most pronounced occupational exposure routes for lead (Pb) are inhalation and gastrointestinal uptake mainly through hand-to-mouth behaviour. Skin absorption has been demonstrated for organic Pb compounds, but less is known about inorganic Pb species. Several legislative bodies in Europe are currently proposing lowering biological exposure limit values and air exposure limits due to new evidence on cardiovascular effects at very low blood Pb levels. In light of this, all exposure routes in occupational settings should be revisited to evaluate how to lower the overall exposure to Pb. METHODS: The aim of the study was to investigate the possible exposure routes in workers operating computer numerical control-machines in a brass foundry and specifically to understand if metal cutting fluids (MCFs) used by the workers could lead to skin absorption of Pb. The different bronze alloys at the facility may contain up to 20% Pb. After obtaining written informed consent from the workers (n = 7), blood, skin wipes, and personal air samples were collected. In addition, MCFs used on the day of exposure measurements were collected for in vitro skin absorption studies using stillborn piglet skin mounted in static Franz diffusion cells (n = 48). All samples were analysed for Pb content using inductively coupled plasma mass spectrometry. RESULTS: Pb air concentration (<0.1-3.4 µg m-3) was well below the Swedish occupational exposure limit value. Blood Pb was in the range of <0.72-33 µg dl-1, and Pb on skin surfaces, after performing normal work tasks during 2 h, was in the range of 0.2-48 µg cm-2. Using the MCFs in diffusion cells showed that skin absorption had occurred at very low doses, and that up to 10% of the Pb content was present in the skin after 24 h exposure. Using these results in the US EPA adult lead model, we could estimate a contribution to blood Pb from the three exposure routes; where hand-to-mouth behaviour yielded the highest contribution (16 µg Pb dl-1 blood), followed by skin absorption (3.3-6.3 µg Pb dl-1 blood) and inhalation (2.0 µg Pb dl-1 blood). CONCLUSIONS: This case study shows that MCF may lead to skin absorption of inorganic Pb and contribute to a systemic dose (quasi-steady state). Furthermore, even though good hand hygienic measures were in place, the workers' skin exposure to Pb is in all likelihood an important contributor in elevating blood Pb levels. Skin exposure should thus be monitored routinely in workers at facilities handling Pb, to help reducing unnecessary occupational exposure.

Cohort profile: Studies of Work Environment and Disease Epidemiology-Infections (SWEDE-I), a prospective cohort on employed adults in Sweden.

The aim of this article is to provide a detailed description of the SWEDE-I cohort, a prospective study designed to investigate work-related risk factors for transmission of viral infections. A total of 2,237 subjects aged 25-64, working and residing in Eskilstuna (central Sweden), enrolled in the study in August 2011. They filled in five detailed questionnaires including information on demography, personal characteristics, work tasks, work place, contact patterns, family structure, health status, physical activity and diet. During a 9-month follow-up period, the participants self-reported-via internet or telephone-any onset of fever, upper respiratory tract infection, or gastroenteritis immediately as they occurred. For each disease episode, the participants were asked to submit a self-sampled nasal swab for viral diagnosis. In total, 1,733 disease reports were recorded and 1,843 nasal swabs were received, of which 48% tested positive for one or more of 14 analyzed viruses. The cohort has been used to date to study diet, sleep and physical activity as determinants for upper respiratory tract infections. Analyses of contact patterns and occupational circumstances as risk factors for the transmission of infections are ongoing. The SWEDE-I study should be seen as a first pioneering effort to provide new insight in the epidemiology and prevention of viral infections. Potential joint collaborations can be discussed with the principal investigators.

Airborne and Dermal Exposure to Polycyclic Aromatic Hydrocarbons, Volatile Organic Compounds, and Particles among Firefighters and Police Investigators.

AIMS: The main aim of this study was to assess dermal exposure to polycyclic aromatic hydrocarbons (PAHs) and airway exposure to PAHs, volatile organic compounds (VOCs; benzene and 1,3-butadiene), and particles among firefighters (FFs) and police forensic investigators (PFIs) in Sweden. METHODS: Active (pump with a filter and sorbent tube) and passive (polyurethane foam -cyl and perkin elmer carbopack-tube) personal air sampling and dermal tape stripping (wrist and collar bone) were performed on seven FF team leaders during training fires and nine PFIs investigating the aftermath of live fire events. In addition, passive personal air sampling was performed on eight FF team leaders during live emergency fires. PAHs and VOCs were analysed using high-resolution gas chromatography low-resolution mass spectrometry. The mass concentration of total dust (particles) was determined using standard gravimetric methods. RESULTS: The air samples showed that the exposure to PAHs, benzene, 1,3-butadiene, and particles was below Swedish occupational exposure limits (OELs). Naphthalene was the predominant PAH in all air samples. Benzene and 1,3-butadiene were more abundant in live emergency fires, which caused higher exposures than the other studied situations. Both gaseous- and particle-associated PAHs were present on skin. The wrists seemed to be less well protected than the collarbone area. CONCLUSIONS: FFs and PFIs are exposed to several hazardous compounds during their work. Air exposures varied considerably between working scenarios. The observed exposures were substantially higher than urban background levels but well below Swedish OELs. The measured dermal PAH exposures were comparable to previously reported doses for US FFs but lower than the exposures reported for Swedish chimney sweeps.

Nickel deposition and penetration into the stratum corneum after short metallic nickel contact: An experimental study.

BACKGROUND: Knowledge about the skin deposition and penetration of nickel into the stratum corneum (SC) after short contact with metallic items is limited. OBJECTIVE: To quantify nickel skin deposition and penetration into the SC after short contact with metallic nickel. METHODS: Sixteen nickel-allergic participants and 10 controls were exposed to 3 pure nickel discs and 1 aluminium disc on each volar forearm for 3 × 10 minutes. Before exposure, 1 forearm was irritated with 0.5% sodium lauryl sulfate under 24-hour occlusion. Immediately, as well as 24 and 72 hours after metallic disc exposure, outer SC layers were removed with adhesive tapes and the nickel content was measured. RESULTS: Nickel deposition and SC penetration capable of eliciting allergic nickel dermatitis were found immediately and after 24 hours. Significantly higher nickel amounts were found on normal skin and in the SC of nickel-allergic participants than in controls both immediately and after 24 hours, and on irritated skin immediately after exposure. CONCLUSIONS: Nickel deposition and SC penetration is considerable after nickel skin exposure of 3 × 10 minutes. Combined with the allergic responses resulting from the same exposures reported previously, this study highlights that short skin exposure to nickel-releasing items may cause allergic nickel dermatitis.

Neglected exposure route: cobalt on skin and its associations with urinary cobalt levels.

OBJECTIVES: Cobalt (Co) exposure is associated with adverse health effects including skin sensitisation, asthma and interstitial lung fibrosis. Exposure to Co in industrial settings is often assessed using air samples or biomonitoring in urine. Skin exposure is rarely measured. Aim of this study was to quantify and compare the importance of Co skin exposure and respiratory exposure in determining urinary Co concentrations. METHODS: Co skin exposure was measured in 76 hard metal workers by acid wipe sampling before and at the end of work shifts. Spot urine was collected during a 24-hour period from the start of a shift. Respiratory exposure was measured by personal inhalable dust sampling during a shift in 30 workers. Co was analysed by inductively coupled plasma mass spectrometry. RESULTS: Quantile regression modelling showed that a doubling of Co on skin before or at the end of shift increased the median urinary concentration of Co by 70% (p<0.001) or 32% (p<0.001), respectively. A doubling of Co in air increased median urinary Co by 38% (p<0.001). Co skin exposures were still significantly associated with urinary Co after excluding a group of workers with high respiratory exposure (33%, p=0.021 and 17%, p=0.002). CONCLUSIONS: The results indicate an association between Co skin exposure and urinary Co concentrations. This should be considered when using urinary Co as a biomarker of exposure.

Contamination of skin and surfaces by cobalt in the hard metal industry.

BACKGROUND: It is well known that hard metal workers have historically been affected by contact allergy to cobalt. Knowledge is sparse about occupational skin exposure to cobalt, in terms of skin doses and sources of exposure, which could be used to improve protection of workers. OBJECTIVES: To improve knowledge about skin doses and sources of skin exposure to cobalt within hard metal production, thereby facilitating better protection of workers. METHODS: Forty workers were sampled on the index finger by acid wipe sampling after 2 hours of work. The samples were analysed with inductively coupled plasma mass spectrometry. Cobalt spot testing was performed in the work environment. RESULTS: The highest skin doses were found among raw material workers. Skin doses among other production workers were also significant. Most office workers had low, but measurable, levels of cobalt on the skin. Glove use varied between workers. Cobalt was found on production equipment, on items in the canteen area, and on handles and buttons throughout the company. CONCLUSIONS: Cobalt skin doses were prominent, and originated from contact with raw materials, sintered materials, and contaminated surfaces. Cobalt was present on surfaces outside production areas. Companies need to identify and reduce skin exposure for protection of workers.

An improved method for determining dermal exposure to polycyclic aromatic hydrocarbons.

Many workers are occupationally exposed to polycyclic aromatic hydrocarbons (PAHs), which may cause various health problems, and some PAHs are known or suspected carcinogens. PAH exposure is primarily monitored by air sampling, but contamination may also occur through dermal exposure. PAHs adsorbed to the skin can be sampled by tape-stripping, but subsequent extraction of sampling tapes in organic solvent also releases diverse co-eluting substances that are difficult to remove before analysis of the PAHs by gas chromatography/mass spectrometry (GC/MS). The objective of this study was to optimise a procedure for analytical clean-up after extraction of 32 PAHs from tape-strips, by dialysis in organic solvent using semipermeable membranes. With triplicate subsamples, the developed method yields acceptable precision and repeatability for both the 32 PAHs, across the concentration range 10-160 ng per sample, and for a certified reference material (urban dust). The optimized clean-up procedure and GC/MS methodology was used to assess PAHs on skin from the lower part of the ventral side of the wrist and just below the collar bone of three firefighters and seven controls (office workers). Several gaseous and particle-bound PAHs were detected in all samples, including controls. Thus, the optimized procedure using semipermeable membranes for clean-up of tape-strip extracts can be used to assess the dermal exposure of both occupational and general populations to multiple PAHs. The results also show that both gaseous and particle-bound PAHs, including alkylated species, may be present on skin.

Evaluation of polyurethane foam passive air sampler (PUF) as a tool for occupational PAH measurements.

Routine monitoring of workplace exposure to polycyclic aromatic hydrocarbons (PAHs) is performed mainly via active sampling. However, active samplers have several drawbacks and, in some cases, may even be unusable. Polyurethane foam (PUF) as personal passive air samplers constitute good alternatives for PAH monitoring in occupational air (8 h). However, PUFs must be further tested to reliably yield detectable levels of PAHs in short exposure times (1-3 h) and under extreme occupational conditions. Therefore, we compared the personal exposure monitoring performance of a passive PUF sampler with that of an active air sampler and determined the corresponding uptake rates (Rs). These rates were then used to estimate the occupational exposure of firefighters and police forensic specialists to 32 PAHs. The work environments studied were heavily contaminated by PAHs with (for example) benzo(a)pyrene ranging from 0.2 to 56 ng m-3, as measured via active sampling. We show that, even after short exposure times, PUF can reliably accumulate both gaseous and particle-bound PAHs. The Rs-values are almost independent of variables such as the concentration and the wind speed. Therefore, by using the Rs-values (2.0-20 m3 day-1), the air concentrations can be estimated within a factor of two for gaseous PAHs and a factor of 10 for particulate PAHs. With very short sampling times (1 h), our method can serve as a (i) simple and user-friendly semi-quantitative screening tool for estimating and tracking point sources of PAH in micro-environments and (ii) complement to the traditional active pumping methods.

Development, validation and testing of a skin sampling method for assessment of metal exposure.

BACKGROUND: Nickel, cobalt and chromium are frequent skin sensitizers. Skin exposure results in eczema in sensitized individuals, the risk being related to the skin dose. OBJECTIVES: To develop a self-sampling method for quantification of skin exposure to metals, to validate the method, and to assess its feasibility. METHODS: Defined metal doses (0.01-5 µg) were applied to the fingers of 5 participants. Skin areas (2 cm2 ) were sampled with 1% HNO3 , either as 0.1 ml on a swab, or as 0.5 ml on a wipe. Furthermore, 17 participants performed self-sampling by swab after 2 h of leisure activity. Samples were extracted in 1% HNO3 and analysed by inductively coupled plasma mass spectrometry. RESULTS: The sampling efficiency by swab was 46%, as compared with 93% for acid wipe sampling, for all tested doses. Most metal from the skin dose was detected in the first swab (33-43%). Despite lower sampling efficiency by swab, skin doses of metals following 2 h of leisure activity without hand washing were quantified in all participants, and ranged from 0.0016 to 0.15 µg/cm2 , from 0.00014 to -0.0020 µg/cm2 and from 0.00048 to -0.027 µg/cm2 for nickel, cobalt, and chromium, respectively. CONCLUSIONS: The results indicate a future potential of skin sampling by swab to detect and monitor metals on skin by self-sampling. This will contribute to better knowledge of metal skin exposure among dermatitis patients, workers, and the general population.

Testing in artificial sweat - Is less more? Comparison of metal release in two different artificial sweat solutions.

Metal release from materials immersed in artificial sweat can function as a measure of potential skin exposure. Several artificial sweat models exist that, to various degree, mimic realistic conditions. Study objective was to evaluate metal release from previously examined and well characterized materials in two different artificial sweat solutions; a comprehensive sweat model intended for use within research, based on the composition of human sweat; and the artificial sweat, EN1811, intended for testing compliance with the nickel restriction in REACH. The aim was to better understand whether there are advantages using either of the sweat solutions in bio-elution testing of materials. Metal release in two different artificial sweat solutions was compared for discs of a white gold alloy and two hard metals, and a rock drilling insert of tungsten carbide at 1 h, 24 h, 1 week and 1 month. The released amount of metal was analysed by means of inductively coupled plasma mass spectrometry. Similar levels of released metals were measured from test materials in the two different artificial sweat solutions. For purposes in relation to legislations, it was concluded that a metal release test using a simple artificial sweat composition may provide results that sufficiently indicate the degree of metal release at skin contact.

Snapshot of cobalt, chromium and nickel exposure in dental technicians.

BACKGROUND: It is not fully understood where and how people are exposed to sensitizing metals. Much can be learnt from studying occupational settings where metals are handled. OBJECTIVES: To quantify cobalt (Co), chromium (Cr) and nickel (Ni) exposure on the skin and in the air, and urine levels, in dental technicians working with tools and alloys that may result in skin and respiratory exposure. METHODS: The metal skin dose was quantified with acid wipe sampling in dental technicians (n = 13). Air exposure was monitored by personal air sampling. Spot urine samples were collected for 24 h. Metals were analysed with inductively coupled plasma mass spectrometry. RESULTS: Before work, Co was detected on the skin of 10 participants (0.00025-0.0039 µg/cm2 ), and Cr (0.00051-0.011 µg/cm2 ) and Ni (0.0062-0.15 µg/cm2 ) on the skin of all participants. After a 2-h period without hand washing, CoCr-exposed participants had more Co on the skin (p = 0.004) than non-CoCr-exposed participants. Co was found in 10 air samples (0.22-155 µg/m3 ), Cr in nine (0.43-71 µg/m3 ), and Ni in four (0.48-3.7 µg/m3 ). Metal urine concentrations were considered to be normal. CONCLUSIONS: Dental technicians were exposed to Co, Cr and Ni on the skin and through the air, which was not reflected in the urine concentrations in this study. Cobalt skin doses may potentially elicit allergic contact dermatitis and cause sensitization.

Extracellular cadmium in the bronchoalveolar space of long-term tobacco smokers with and without COPD and its association with inflammation.

Tobacco contains cadmium, and this metal has been attributed a causative role in pulmonary emphysema among smokers, although extracellular cadmium has not to date been quantified in the bronchoalveolar space of tobacco smokers with or without COPD. We determined whether cadmium is enhanced in the bronchoalveolar space of long-term tobacco smokers with or without COPD in vivo, its association with inflammation, and its effect on chemokine release in macrophage-like cells in vitro. Bronchoalveolar lavage (BAL), sputum, and blood samples were collected from current, long-term smokers with and without COPD and from healthy nonsmokers. Cadmium concentrations were determined in cell-free BAL fluid using inductively coupled plasma mass spectrometry. Blood monocyte-derived macrophages were exposed to cadmium chloride in vitro. Depending upon the type of sample, molecular markers of inflammation were quantified either as protein (enzyme-linked immunosorbent assay) or as mRNA (real-time polymerase chain reaction). Cadmium concentrations were markedly increased in cell-free BAL fluid of smokers compared to that of nonsmokers (n=19-29; P<0.001), irrespective of COPD. In these smokers, the measured cadmium displayed positive correlations with macrophage TNF-α mRNA in BAL, neutrophil and CD8(+) cell concentrations in blood, and finally with IL-6, IL-8, and MMP-9 protein in sputum (n=10-20; P<0.05). The cadmium chloride exposure caused a concentration-dependent increase in extracellular IL-8 protein in monocyte-derived macrophages in vitro. In conclusion, extracellular cadmium is enhanced in the bronchoalveolar space of long-term smokers and displays pro-inflammatory features. Its pathogenic role in tobacco-induced disease deserves further evaluation.