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Resorcinol is a suspected endocrine disruptor that affects thyroid function by inhibiting thyroxin peroxidase. It may also have an impact on iodine uptake. Resorcinol has various uses; for example in the manufacture of rubber products and in wood adhesives, flame retardants, UV stabilizers, and dyes. It is also used in personal care products such as hair colorants, anti-acne preparations, and peels. The aim of this study was to assess both environmental background exposure and occupational exposure to resorcinol in Finland. We investigated occupational exposure in hairdresser work and in the manufacture of tyres, adhesive resins and glue-laminated timber by biomonitoring total resorcinol concentration in urine samples. The biomonitoring results were compared to the urinary levels of occupationally non-exposed volunteers, and to the biomonitoring equivalent (BE), which we estimated on the basis of the EFSA's acceptable daily intake (ADI) value for resorcinol. Almost all the urine samples (99%) of the non-occupationally exposed volunteers contained measurable amounts of resorcinol. The urinary resorcinol data were rather scattered, and the resorcinol concentrations among women (GM 84 μg/l, 95th percentile 2072 μg/l) were clearly higher than the respective concentrations among men (GM 35 μg/l, 95th percentile 587 μg/l). The reason for this difference remains unclear. Although the two highest results exceeded the BE of 4 mg/l calculated on the basis of the EFSA's ADI, the 95th percentile of the occupationally non-exposed volunteers' results remained well below the BE among both males and females. According to the results, hairdressers' exposure to resorcinol was at the same level as that of the reference population of occupationally non-exposed volunteers. All hairdresser's values remained below the BE for resorcinol. The urinary resorcinol levels of the industrial workers were also at the same level as those of the reference population. We observed slight increases in the post-shift and evening samples of those working in the manufacture of tyres and adhesive resins. The results of some workers in the tyre manufacturing company exceeded the 95th percentile of non-occupationally exposed males, which was used as a biological guidance value for occupational exposure. Moreover, in this case exposure was below the health-based biomonitoring equivalents. All the air samples collected in the companies contained very low resorcinol concentrations. It should be noted that the sample sizes for the male controls and industrial groups were small.

8-hydroxy-2'-deoxyguanosine (8-OHdG) is a widely used biomarker of oxidative stress in research related to DNA, protein damage as well as lipid peroxidation. HPLC-MS/MS with electrospray ionization (ESI) and the use of isotopically labelled 8-OHdG as an internal standard allows a simple quantification of 8-OHdG in urine samples. HPLC separation utilized the peak cutting technique and a 1.5 mmx120 mm analytical anion exchange column. Novel method entails only minimal sample handling including the addition of a buffer and an internal standard followed by centrifugation before the samples are ready for analysis. The levels of 8-OHdG in human urine samples (n=246) varied from 0.16 to 16.48 microg/L and the corresponding creatinine-normalized values were ranged from 0.49 to 14.27 microg of 8-OHdG/g creatinine. The correlation between the developed HPLC-MS/MS method and the existing HPLC-EC method was good with an R2 value of 0.8707.

Methylhexahydrophthalic anhydride (MHHPA) is a hardener for hot-cured epoxy resins employed as insulators in the electric industry. MHHPA has only been measured as an ingredient with other alicyclic anhydrides, albeit there are also large processes which use only MHHPA. We collected MHHPA vapour in a set of devices: Teflon filter, glass spiral, TenaxTA tube connected consecutively together. Elution was performed with a solvent mixture of methyl-tert-butyl ether (70%), acetonitrile (30%), and acetic anhydride (0.5%). By capillary GC-ECD, the regression was linear (0.9994) in the practical low concentration range of 0.04-1 microg ml(-1) being equal to 0.001-0.035 mg m(-3) in 30 l of air. The exposure was measured in two factories manufacturing electric appliances. The assembled objects were first impregnated with a liquid epoxy/hardener mixture, and then the resin hardened at elevated temperature. In condenser manufacturing, the operators' 8 h exposure ranged from 0.068 to 0.118 mg m(-3), and the short-term exposure was during operation at ovens mean 1.90 mg m(-3). The impregnation of coiled resistors and transfer of them to ovens caused the worst exposures, short-term mean 3.846 mg m(-3) and long-term mean 2.191 mg m(-3). During the 'baking', the ovens were closed and evacuated, but when the hot objects were moved out of the ovens, they continued during chilling to emit MHHPA, mean 0.366 mg m(-3). In the adjacent areas, assembling, control rooms, offices, the exposure was still significant, 0.017-0.043 mg m(3), due to leaks from the high exposure areas. Mechanical general ventilation and local exhausts were functioning. Respirators were available for short supervising of the hot equipment.

The product ion mass spectra (collisionally induced dissociation mass spectra) of 12 different cyclosporins modified at every N-methylated amino acid residue with respect to cyclosporin A were compared and the effect of N-demethylation on ring opening mechanisms was evaluated. The four preferential protonation sites were identified in [MeBmt(1)]-cyclosporins. Three sites represented the N-methylated nitrogens of Sar(3), MeLeu(6) and MeLeu(9), while the remaining one represented the lactone group formed by the intramolecular N,O-acyl shift. Selective N-demethylation resulted either in the deletion of the entire fragment ion series or its substantial attenuation. The structures of three new natural cyclosporins in the study were supported by NMR data.

A basic need for a protein-based dosimeter is a purified protein. In this communication we present an isolation protocol and an HPLC-based assay which allows one to determine the purity of the isolated albumin. A total of 168 human blood samples were collected from workers of a benzene processing plant and from nearby countryside at Kohtla-Jarve, Estonia. Albumin was isolated from plasma by sequential precipitation and the purity was determined by HPLC. The amount of albumin present in plasma varied between the individuals, being 147 ± 26 mg/5 ml (n=168), which is about 59% of plasma albumin. However, the isolated albumin was highly pure (100.9 ± 8.2%, n=5). All albumin samples analyzed demonstrate two peaks in HPLC analysis. The two peaks detected were collected and subjected to MS analysis, which demonstrates a difference of 120 mass units between the two albumin products isolated. We have developed an assay, which is easy to carry out and is not too labor intense. The HPLC analysis can be applied to confirm the purity of the isolated albumin as well as to confirm the quantity of the albumin in samples.

The use of chlorophenol-containing antistain agents (e.g., Ky5, a wood preservative) ceased in Finland at the end of the 1980s, after 5 decades of use. Exposure of workers to the impurities in these agents (i.e., polychlorinated dibenzo-p-dioxins [PCDDs] and dibenzofurans [PCDFs]) was assessed at three sawmills at which personnel used a sodium chlorophenate product as an antistain agent. Given that compounds accumulate in body fat and their half-lives in humans are long, we could determine 2,3,7,8-substituted PCDDs and PCDFs 5-9 y after the last exposure occurred. We used high-resolution gas chromatography/high-resolution mass spectrometry to determine PCDDs/PCDFs in plasma from 39 Ky5-exposed workers and 18 nonexposed workers. The average total plasma concentration of PCDD/PCDF of the Ky5-exposed workers at the three sawmills were 1018, 945, and 1165 pg/g fat, and corresponding concentrations in the nonexposed workers were 743, 1124, and 844 pg/g fat, respectively. We found no significant differences in total levels between Ky5-exposed workers and nonexposed workers. However, concentrations of the 1,2,3,4,6,7,8-HpCDF isomer were significantly higher (p.01) among the Ky5-exposed workers at all three sawmills (averages of 224, 99, and 148 pg/g fat) than among their respective nonexposed workers (averages of 43, 48, and 44 pg/g fat). These results indicate that workers had handled Ky5. When we expressed concentration levels in international toxic equivalents (I-TEQs), the mean total I-TEQ PCDD/PCDF of Ky5-exposed workers was significantly lower at one of the sawmills (average = 42 pg I-TEQ/g) than at the other two sawmills (averages of 64 and 62 pg I-TEQ/g)(p.05). Nevertheless, total concentrations at the sawmills studied were within the range of background levels in the general population.

In vitro toxicological studies together with atomistic molecular dynamics simulations show that occupational co-exposure with C-60 fullerene may strengthen the health effects of organic industrial chemicals. The chemicals studied are acetophenone, benzaldehyde, benzyl alcohol, m-cresol, and toluene which can be used with fullerene as reagents or solvents in industrial processes. Potential co-exposure scenarios include a fullerene dust and organic chemical vapor, or a fullerene solution aerosolized in workplace air. Unfiltered and filtered mixtures of C-60 and organic chemicals represent different co-exposure scenarios in in vitro studies where acute cytotoxicity and immunotoxicity of C-60 and organic chemicals are tested together and alone by using human THP-1-derived macrophages. Statistically significant co-effects are observed for an unfiltered mixture of benzaldehyde and C-60 that is more cytotoxic than benzaldehyde alone, and for a filtered mixture of m-cresol and C-60 that is slightly less cytotoxic than m-cresol. Hydrophobicity of chemicals correlates with co-effects when secretion of pro-inflammatory cytokines IL-1 beta and TNF-alpha is considered. Complementary atomistic molecular dynamics simulations reveal that C-60 co-aggregates with all chemicals in aqueous environment. Stable aggregates have a fullerene-rich core and a chemical-rich surface layer, and while essentially all C-60 molecules aggregate together, a portion of organic molecules remains in water.

Blood samples from 34 workers at a pulp and paper mill and from 14 control persons were analysed for 2,3,7,8-substituted PCDDs and PCDFs. There were no statistically significant differences in total lipid-adjusted PCDD/PCDF concentrations, expressed as toxic equivalents, in blood plasma between the potentially exposed bleaching plant or paper mill workers and the controls. The mean level was 61 pg/g I-TEQ in bleaching plant workers, 60 pg/g I-TEQ in paper mill workers and 49 I-TEQ pg/g in controls. Regarding the concentrations of individual isomers, however, there was an indication that the blood plasma concentrations might be affected by the living and working environment.

The concentrations of airborne 2,3,7,8-substituted polychlorinated dibenzo- p -dioxins and dibenzofurans measured at a pulp and paper mill ranged from 0.04 to 1.9 pg/m 3 . The paper mill used softwood and hardwood pulp which was bleached with solely chlorine dioxinde in the first chlorination stage. The chlorinated furans dominated in all samples, while very few dioxins were detected. No 2,3,7,8-tetrachlorodibenzo- p -dioxin was detected. The highest concentration was measured for 1,2,3,4,6,7,8-heptachlorodibenzofuran, which was present in all samples. The toxic equivalent concentrations varied between 0.002 and 0.2 pg/m 3 using the international toxic equivalency factors. The congener profile of a paper dust sample was similar to that of the corresponding air samples.

Waste electrical and electronic equipment (WEEE) contains various hazardous substances such as flame retardants (FRs). Inhalation exposures to many FRs simultaneously among WEEE recycling site workers have been little studied previously. The breathing zone airborne concentrations of five brominated FR compounds tetrabromobisphenol-A (TBBP-A), decabromodiphenylethane (DBDPE), hexabromocyclododecane, 1,2-bis(2,4,6-tribromophenoxy)ethane, hexabromobenzene, and one chlorinated FR (Dechlorane Plus®) were measured at four electronics recycling sites in two consecutive years. In addition, concentrations of polybrominated diphenyl ethers (PBDEs) and polybrominated biphenyls were measured. The three most abundant FRs in personal air samples were PBDEs (comprising mostly of deca-BDE), TBBP-A, and DBDPE, with mean concentrations ranging from 21 to 2320 ng m(-)(3), from 8.7 to 430 ng m(-3), and from 3.5 to 360 ng m(-3), respectively. At two of the sites, the emission control actions (such as improvements in ventilation and its maintenance and changes in cleaning habits) proved successful, the mean levels of FRs in personal samples being 10-68 and 14-79% of those from the previous year or alternatively below the limit of quantification. At the two remaining sites, the reductions in FR exposures were less consistent. The concentrations reported may pose a health hazard to the workers, although evaluation of the association between FR exposure and adverse health effects is hampered by lacking occupational exposure limits. Therefore, the exposures should be minimized by adequate control measures and maintaining good occupational hygiene practice.

Toluene diisocyanate (TDI) and 4,4′-methylenediphenyl diisocyanate (MDI), used in the production of polyurethane foam, are well known for their irritating and sensitizing properties. Contradictory results have been obtained on their genotoxicity. We investigated the genotoxicity and protein binding of inhaled TDI and MDI in mice by examining micronucleated polychromatic erythrocytes (PCEs) in bone marrow and peripheral blood and TDI- and MDI-derived adducts in hemoglobin. Male C57Bl/6J mice (8 per group) were exposed head-only to TDI vapour (mean concentrations 1.1, 1.5, and 2.4 mg/m3; the mixture of isomers contained, on the average, 63% 2,4-TDI and 37% 2,6-TDI) or MDI aerosol (mean concentrations 10.7, 20.9 and 23.3 mg/m3), during 1 h/day for 5 consecutive days. Bone marrow and peripheral blood were collected 24 h after the last exposure. Inhalation of TDI caused sensory irritation (SI) in the upper respiratory tract, and cumulative effects were observed at the highest exposure level. Inhalation of MDI produced SI and airflow limitation, and influx of inflammatory cells into the lungs. Hemoglobin adducts detected in the exposed mice resulted from direct binding to globin of 2,4- and 2,6-TDI and MDI, and dose-dependent increases were observed especially for 2,4-TDI-derived adducts. Adducts originating from the diamines of TDI (toluene diamine) or MDI (methylene dianiline) were not observed. No significant increase in the frequency of micronucleated PCEs was detected in the bone marrow or peripheral blood of the mice exposed to TDI or MDI. The ratio of PCEs and normochromatic erythrocytes (NCEs) was reduced at the highest concentration of MDI, and a slight reduction of the PCE/NCE ratio, dependent on cumulative inhaled dose, was also seen with TDI. Our results indicate that inhalation of TDI or MDI (1 h/day for 5 days), at levels that induce toxic effects and formation of TDI- or MDI-specific adducts in hemoglobin, does not have detectable genotoxic effects in mice, as studied with the micronucleus assay.

Polychlorinated dibenzodioxins, dibenzofurans and non-ortho-coplanar biphenyls were analyzed in blood of workers exposed to contaminated soil dust in a laboratory room. Their levels in blood (n = 7) were compared with those of controls (n = 3). Average PCDD and PCDF levels in blood, expressed in International 2378-TCDD toxicity equivalence (TEQ) levels, were 23 pg and 20 pg TEQ/g blood lipids in exposed and controls, respectively. For coplanar PCBs, levels were 7.4 pg TEQ/g blood lipids exposed compared to 7.7 pg TEQ/g blood lipids in controls. The results of this study indicate that the exposure has not significantly increased the levels of PCDDs, PCDFs and non-ortho-PCBs in blood.

The occurrence of volatile halogenated compounds in spent liquors from kraft softwood and hardwood pulp bleaching processes was studied. The identity of the low-molecular-mass constituents was verified by capillary gas chromatography—mass spectrometry using an NBS/Wiley reference database and mass spectra of reference compounds. The purgeable fraction of the first chlorination stage of the softwood pulp contained numerically most of the organohalogen compounds detected. The ratio of chlorine to chlorine dioxide applied at this stage greatly affected the formation of the compounds. Identity was confirmed for fourteen components, of which two, dichloroacetonitrile and trichloromethanesulphonyl chloride, have not been previously identified in, e.g., bleach kraft effluents. The most abundant volatile compounds were chloroform, 1,1,1-trichloropropanone, trichloromethanesulphonyl chloride, 1,1,2,3,3-pentachloro-1-propene and pentachloropropanone. Several of these volatile compounds are known mutagens or suspected carcinogens.

A new method was developed to assess environmental tobacco smoke in air. The method is based on passive sampling and subsequent measurement of the concentration of 3-ethenylpyridine, a vapor-phase compound specific to tobacco smoke. Air samples were collected using a 3M organic vapor monitor. Tests were carried out in a dynamic chamber to determine the sampling rate (25.7 cm3/min). 3-Ethenylpyridine was desorbed from the sampler with 1 mL of pyridine/toluene mixture. 3-Ethenylpyridine was quantified by gas chromatography/mass spectrometry. The limit of detection was 0.01 microgram/sample, corresponding to a concentration of 0.27 microgram/m3 air calculated for a sampling period of 24 h. Field measurements were carried out to test the performance of the method. Mean concentrations ranging from 1.3 to 5.3 micrograms/m3 were measured for 3-ethenylpyridine in smoking environments, but no 3-ethenylpyridine was detected in nonsmoking environments. Active sampling using charcoal tubes was used as a reference method in the chamber tests and field measurements. Individual exposures can be easily and accurately measured by means of the passive sampler. Because of simple sample treatment, the method is also well-suited for large-scale monitoring of environmental tobacco smoke.