OBJECTIVE: The principal aim of the study was to estimate the level of exposure to organic solvents of graffiti removers, and to identify the chemicals used in different cleaning agents. A secondary objective was to inform about the toxicity of various products and to optimise working procedures. METHODS: Exposure to organic solvents was determined by active air sampling and biological monitoring among 38 graffiti removers during an 8-h work shift in the Stockholm underground system. The air samples and biological samples were analysed by gas chromatography. Exposure to organic solvents was also assessed by a questionnaire and interviews. RESULTS: Solvents identified were N-methylpyrrolidone (NMP), dipropylene glycol monomethyl ether (DPGME), propylene glycol monomethyl ether (PGME), diethylene glycol monoethyl ether (DEGEE), toluene, xylene, pseudocumene, hemimellitine, mesitylene, ethylbenzene, limonene, nonane, decane, undecane, hexandecane and gamma-butyrolactone. The 8-h average exposures [time-weighted average (TWA)] were below 20% of the Swedish permissible exposure limit value (PEL) for all solvents identified. In poorly ventilated spaces, e.g. in elevators etc., the short-term exposures exceeded occasionally the Swedish short-term exposure limit values (STEL). The blood and urine concentrations of NMP and its metabolites were low. Glycol ethers and their metabolites (2-methoxypropionic acid (MPA), ethoxy acetic acid (EAA), butoxy acetic acid (BAA), and 2-(2-methoxyethoxy) acetic acid (MEAA)) were found in low concentrations in urine. There were significant correlation between the concentrations of NMP in air and levels of NMP and its metabolites in blood and urine. The use of personal protective equipment, i.e. gloves and respirators, was generally high. CONCLUSIONS: Many different cleaning agents were used. The average exposure to solvents was low, but some working tasks included relatively high short-term exposure. To prevent adverse health effects, it is important to inform workers about the health risks and to restrict the use of the most toxic chemicals. Furthermore, it is important to develop good working procedures and to encourage the use of personal protection equipment.
OBJECTIVE: To assess the absorption of dietary selenium in humans, especially of milk selenium. DESIGN:: 1-day meal studies in subjects with ileostomy. SETTING: Hospital outpatient clinics. SUBJECTS: Three subjects in the pilot study and nine subjects in the main study (eight men/ four women). INTERVENTION: Different beverages, 1 l/day, were given in addition to basal diets (soft drink, 1 week; low-fat milk, 3 weeks; fermented low-fat milk, 3 weeks and soft drink, 1 week). Ileostomy effluents were collected during the last 2 days in each of the four periods. RESULTS: On days when the subjects were given 1 l of low-fat milk, the estimated fractional absorption of total dietary selenium was 65.5 (2.3)% (mean (s.d.), n=18), which was similar to the value when fermented low-fat milk was given (64.1 (3.2)%). However, both the calculated amount of milk selenium absorbed (10.9 (2.4) vs 9.4 (1.7) microg selenium) and its fractional absorption (73.3 (16.1) vs 64.1 (11.2)%, n=18) were significantly higher for milk than for fermented milk. CONCLUSIONS: Selenium from milk and other sources is well absorbed in subjects with ileostomy. The real absorption may be even higher than the values shown.
The aims were to study the toxicokinetics of 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) in blood and urine after exposure to N-methyl-2-pyrrolidone (NMP) and to study the suitability of 5-HNMP as a biomarker for assessing NMP exposure.
Six male volunteers were exposed for 8 hours to NMP concentrations of 0, 10, 25, and 50 mg/m3. Blood and urine were sampled before, during, and up to 40 hours after exposure. Aliquots of urine and plasma were purified, derivatized, and analyzed for 5-HNMP on a gas chromatograph/mass spectrometer in the electron impact mode.
The mean plasma concentration [P-(5-HNMP)] after 8-hour NMP exposure to 10, 25, and 50 mg/m3 was 8.0, 19.6, and 44.4 micromol/l, respectively. The mean urinary concentration [U-(5-HNMP)] for the 2 last hours of exposure was 17.7, 57.3, and 117.3 mmol/mol creatinine, respectively. The maximal P-(5-HNMP)and U-(5-HNMP) concentrations occurred 1 hour and 0-2 hours, respectively, after the exposure. The half-times of P-(5-HNMP) and U-(5-HNMP) were 6.3 and 7.3 hours, respectively. The 5-HNMP urinary concentrations were 58% of the calculated retained dose. There was a close correlation (r) between P-(5-HNMP) (r=0.98) and U-(5-HNMP) (r=0.97) with NMP exposure.
5-HNMP is an excellent biomarker for assessing exposure to NMP. Its plasma and urinary half-times (6-7 hours), the minimal risk for contamination during sampling in occupational settings, and the close correlation of P-(5-HNMP) and U-(5-HNMP) with NMP exposure makes 5-HNMP suitable for monitoring exposure to NMP. 5-HNMP in plasma is recommended.
A 25% lower cancer mortality was found for 1360 Swedish fishermen who fished on the Baltic Sea than for the general population. The fishermen consumed twice as much fish as the population in the same county. In spite of the low overall cancer mortality, increased mortality from myeloma, as well as increased incidences of gastric carcinoma and squamous cell cancer of the skin and lips, was observed in the cohort. The decrease in risk for ischemic heart disease was not significant. Whether the dietary intake of fatty acids and selenium from fish contributed to the decreased risk was difficult to evaluate. Moreover, whether the consumption of fish from the Baltic Sea, contaminated with, for example, polychlorinated dioxins and dibenzofurans and other persistent organochlorine substances, contributed to the observed increased specific cancer risks is not known. However, the net health effect of high fish consumption from the Baltic Sea seems to be positive.
The intake of trans fatty acids by subjects adhering to the normal Swedish diet or to different vegetarian regimes was studied, using chemical analysis of duplicate portions. Trans-octadecenoic acid was 5.0, 3.9, and 1.8% of dietary fatty acid in the normal, lactovegetarian, and vegan diets, respectively, corresponding to 2.0, 1.3, and 0.5% of energy intake. The results are related to the content of trans-octadecenoic acid in some edible fats.
This study examined a cohort of 1,164 males who, during the period 1927-1981, had been employed for 3 months or more in an industry that produced objects from stainless steel. These workers were exposed to the dust of grinding materials, grinding agents, and stainless steel. From 1975 to 1980, measurements of the total dust in the workroom air have shown levels of about one mg/m3 (consisting of chromium at about 0.1 mg/m3 and nickel at about 0.05 mg/m3) during grinding and several mg/m3 (chromium at about 0.01 mg/m3 and nickel at about 0.005 mg/m3) during polishing. Before 1950, the concentrations were probably considerably higher. Compared to a local reference population, a decrease in mortality (63 observed deaths, standardized mortality (SMR) = 0.79, 95% confidence limits CL = 0.61, 1.01) took place during the 1951-1983 observation period among 318 subjects who had been employed for at least five years, allowing a latency period of at least 20 years. Mortality from cancer of the colon/rectum increased (observed deaths = 6, SMR = 2.47, CL = 0.97, 5.58). The mortality from nonmalignant pulmonary disease did not increase (SMR = 0.29, CL = 0.01, 1.81). During the observation period (1958-1983), there was no significant overall excess of tumors (observed cases = 33, standardized morbidity [SMR] = 1.09, CL = 0.76, 1.54). However, tumor morbidity of the colon/rectum (observed 11, SMR = 2.83, CL = 1.47, 5.19) significantly increased. There were no cases of respiratory cancer (expected 4.7, CL = 0, 0.21). Thus, the results indicate an increased risk of intestinal cancer.(ABSTRACT TRUNCATED AT 250 WORDS)
Since fish is a food rich in selenium in Sweden, selenium status among healthy adults was studied after a change to a diet containing 150-200 g of fish per day. In two experiments the fish diet was maintained for 6 and 11 weeks. The mean increase in plasma selenium was 0.13 mumol/l (13%). Most of the increase was evident already after 3 weeks. In previous studies of the same individuals this diet caused a delay in primary haemostasis and a decrease in platelet aggregability. There was no apparent temporal relationship between the increase in plasma selenium and the increase in bleeding time and the proportion of eicosapentaenoic acid in platelet or plasma phosphatidylcholine. Further analysis is necessary to distinguish the effects of fish fatty acids and selenium on haemostatic functions.
Different healthy food patterns may modify cardiometabolic risk. We investigated the effects of an isocaloric healthy Nordic diet on insulin sensitivity, lipid profile, blood pressure and inflammatory markers in people with metabolic syndrome.
We conducted a randomized dietary study lasting for 18-24 weeks in individuals with features of metabolic syndrome (mean age 55 years, BMI 31.6 kg m(-2) , 67% women). Altogether 309 individuals were screened, 200 started the intervention after 4-week run-in period, and 96 (proportion of dropouts 7.9%) and 70 individuals (dropouts 27%) completed the study, in the Healthy diet and Control diet groups, respectively. Healthy diet included whole-grain products, berries, fruits and vegetables, rapeseed oil, three fish meals per week and low-fat dairy products. An average Nordic diet served as a Control diet. Compliance was monitored by repeated 4-day food diaries and fatty acid composition of serum phospholipids.
Body weight remained stable, and no significant changes were observed in insulin sensitivity or blood pressure. Significant changes between the groups were found in non-HDL cholesterol (-0.18, mmol L(-1) 95% CI -0.35; -0.01, P = 0.04), LDL to HDL cholesterol (-0.15, -0.28; -0.00, P = 0.046) and apolipoprotein B to apolipoprotein A1 ratios (-0.04, -0.07; -0.00, P = 0.025) favouring the Healthy diet. IL-1 Ra increased during the Control diet (difference -84, -133; -37 ng L(-1) , P = 0.00053). Intakes of saturated fats (E%, beta estimate 4.28, 0.02; 8.53, P = 0.049) and magnesium (mg, -0.23, -0.41; -0.05, P = 0.012) were associated with IL-1 Ra.
Healthy Nordic diet improved lipid profile and had a beneficial effect on low-grade inflammation.
In some regions, including the Baltic Sea, fatty fish such as salmon and herring contain high levels of polychlorinated dibenzodioxins and dibenzofurans. We investigated human exposure to these potentially toxic substances in relation to the consumption of fish from the Baltic Sea.
Plasma levels of 10 different dibenzofurans and 7 dioxins were analyzed in three groups of Swedish men: one group with a high intake of fish (fish eaten almost daily; n = 11), one with a moderate intake of fish (about once per week; n = 9), and one with no consumption of fish (usually because of allergy; n = 9).
Plasma levels of several of the compounds we measured were higher in the men with a high intake of fish than in those who consumed moderate amounts, and the levels were higher in those who ate moderate amounts of fish than in those who ate none. The median amounts of the most toxic dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin) were 8.0 pg per gram of plasma lipid (range, 2.0 to 13) in the high-intake group, 2.6 pg per gram (range, 1.2 to 4.2) in the moderate-intake group, and 1.8 pg per gram (range, 1.0 to 2.5) in the nonconsumers (P = 0.001 and 0.02, respectively). There were consistent and statistically significant associations between the reported amount of fish eaten and the plasma levels of several of the dibenzofurans and dioxins.
Contaminated fish such as those from the Baltic Sea are an important source of exposure to polychlorinated dibenzofurans and dibenzodioxins in persons who eat fish regularly. However, the clinical consequences of such exposure remain uncertain.
Fatty acid composition of serum phosphatidylcholine was studied in subjects living in the same area and selected for high consumption of fat fish, high consumption of lean fish, moderate or no consumption of fish. The proportion of eicosapentaenoic acid (20:5) in serum phosphatidylcholine was fourfold higher, and that of docosahexaenoic acid (22:6) twofold higher among high consumers of fish compared to non-consumers, and these proportions were also higher in fat fish consumers than in high consumers of lean fish, and in moderate consumers compared to non-consumers. In the whole group the intake of fat fish was correlated to the proportions of 20:5, 22:6 and total n-3 fatty acids in serum phosphatidylcholine. The estimated intake of total n-3 fatty acids from fish was highly correlated to the proportions of these fatty acids in serum phosphatidylcholine (r = 0.87). Plasma triglyceride concentration was lower among high fat fish consumers than in other groups, but no differences between groups were observed for concentration of cholesterol, LDL cholesterol, and HDL cholesterol. It is concluded that subjects who consume high amounts of fat fish in their normal diet attain approximately the same proportions of n-3 fatty acids in serum phosphatidylcholine as reported for subjects taking fish oil supplements, and that fatty acid composition of serum lipids can be used as a marker of intake of fat fish.