Ultraviolet radiation and skin cancer risk in offshore workers.

BACKGROUND: Excess skin cancer mortality and incidence have been reported among both land-based and offshore petroleum workers. The association between skin cancer and ultraviolet radiation (UVR) exposure has not been examined in these workers, although they have long off-duty periods and high average income that may allow travelling to sunny destinations. In addition, they have access to solariums free of charge on many accommodation platforms. AIMS: To prospectively examine risk of incident cutaneous melanoma (CM) and non-melanoma skin cancer (NMSC), according to sun-tanning habits with adjustment for aromatic hydrocarbon exposure. METHODS: A cohort of men employed offshore from 1965 to 1999 was linked through the Cancer Registry of Norway 1999-2012. Cox regression adapted to a stratified case-cohort design was used to estimate hazard ratios with 95% confidence intervals. RESULTS: The cohort included 24917 men. During 13.5 years of follow-up, 112 CMs and 70 NMSCs occurred. A positive dose-response relationship was seen between sunburn frequency and risk of CM (Ptrend < 0.05) and NMSC (Ptrend < 0.01). Solarium use both before and after age 20 was related to increased risk of NMSC. Sunscreen use was associated with increased risk of NMSC (Ptrend < 0.001). CONCLUSIONS: UVR exposure seems to be a significant contributor to the elevated risk of skin cancer observed in North Sea offshore workers. The positive association between solarium use and NMSC risk adds to the growing body of literature on artificial UV devices as carcinogenic.

Benzene exposure and risk of lymphohaematopoietic cancers in 25 000 offshore oil industry workers.

BACKGROUND: The aim of this work was to examine the risk of lymphohaematopoietic (LH) cancer according to benzene exposure among offshore workers. METHODS: Cancer registry data were used to identify 112 cancer cases diagnosed during 1999-2011 in a cohort of 24 917 Norwegian men reporting offshore work between 1965 and 1999. Analyses were conducted according to a stratified case-cohort design with a reference subcohort of 1661 workers. Cox regression was used to estimate hazard ratios with 95% confidence intervals, adjusted for other benzene exposure and smoking. RESULTS: Most workers were exposed to benzene for <15 years. The upper range values of average intensity and cumulative exposure were estimated to 0.040 p.p.m. and 0.948 p.p.m.-years, respectively. Risks were consistently elevated among exposed workers for all LH cancers combined and for most subgroups, although case numbers were small and yielded imprecise risk estimates. There was evidence of dose-related risk patterns according to cumulative exposure for acute myeloid leukaemia (AML), multiple myeloma (MM) (P trends 0.052 and 0.024, respectively), and suggestively so for chronic lymphocytic leukaemia (CLL) according to average intensity (P trend 0.094). CONCLUSIONS: Our results support an association between cumulative and intensity metrics of low-level benzene exposure and risk for AML, MM, and suggestively for CLL.

Health complaints after a malodorous chemical explosion: a longitudinal study.

BACKGROUND: Physical and psychological symptoms are prevalent in populations recently affected by industrial accidents. Follow-up studies of human health effects are scarce, and as most of them focus on residents, little is known about the long-term health effects among workers exposed to malodorous emissions following a chemical explosion. AIMS: To assess whether subjective health complaints (SHC) among workers declined over a 4-year period after an oil tank explosion that emitted malodorous sulphurous compounds. METHODS: A longitudinal survey from 2008 (18 months after the explosion) to 2012, performed using the SHC inventory. Questionnaire data were analysed using a linear mixed effects model. RESULTS: There was a decrease in SHCs among the exposed workers, but they still had significantly more subjective neurological symptoms (P < 0.01) compared with controls, adjusted for gender, age, smoking habits, educational level and proximity to the explosion. CONCLUSIONS: Although there was a downward trend in SHCs among exposed workers in the follow-up period, they reported more subjective neurological complaints than controls. Symptoms may be mediated by perceived pollution and health risk perception, and adaptation or anxiety may cause a chronic effect, manifested by a dysfunctional and persistent neuropsychological response.

Reduction in respiratory symptoms among cement workers: a follow-up study.

BACKGROUND: Several studies have reported associations between cement dust exposure and adverse respiratory health effects, but there are few follow-up studies and no studies of respiratory health effects following dust control measures. AIMS: To assess changes in respiratory health among cement workers and unexposed controls after 1 year in a factory implementing a health and safety campaign with the main aim to increase use of personal protective equipment. Earlier the factory had made technical improvements which had reduced dust levels. METHODS: Respiratory questionnaire interviews and personal total dust exposure assessments were conducted in 2010 and 2011. RESULTS: A total of 171 cement workers and 98 controls participated in the study in 2010. The prevalence of cough, cough with sputum, dyspnoea and wheeze among the 134 exposed workers assessed at follow-up in 2011 was significantly lower than in 2010, but not among 63 controls followed up in 2011. Total dust exposure levels among exposed workers did not differ between 2010 and 2011. CONCLUSIONS: The prevalence of respiratory symptoms among cement workers was reduced after 1 year of follow-up following an intervention campaign to improve use of personal protective equipment.

Can air pollution affect tear film stability? A cross-sectional study in the aftermath of an explosion accident.

BACKGROUND: After an explosion and fire in two tanks containing contaminated oil and sulphur products in a Norwegian industrial harbour in 2007, the surrounding area was polluted. This caused an intense smell, lasting until the waste was removed two years later. The present study reports examinations of tear film break up time among the population. The examinations were carried out because many of the people in the area complained of sore eyes. The purpose of the study was to assess the relationship between living or working close to the polluted area and tear film stability one and a half years after the explosion. METHODS: All persons working or living in an area less than six kilometres from the explosion site were invited to take part in the study together with a similar number of persons matched for age and gender living more than 20 kilometres away. Three groups were established: workers in the explosion area and inhabitants near the explosion area (but not working there) were considered to have been exposed, and inhabitants far away (who did not work in the explosion area) were considered to be unexposed. A total of 734 people were examined, and the response rate was 76 percent. Tear film stability was studied by assessing non-invasive break-up time (NIBUT) using ocular microscopy. In addition Self-reported Break Up Time (SBUT) was assessed by recording the time the subject could keep his or hers eyes open without blinking when watching a fixed point on a wall. Background information was obtained using a questionnaire. Non-parametric Wilcoxon-Mann-Whitney-tests with exact p-values and multiple logistic regression analyses were performed. RESULTS: Both NIBUT and SBUT were shorter among the male exposed workers than among the inhabitants both near and far away from the explosion area. This was also found for SBUT among males in a multiple logistic regression analysis, adjusting for age and smoking. CONCLUSIONS: Reduced tear film stability was found among workers in an area where an explosion accident had occurred.

Acute suppression of serum IgM and IgA in tank workers exposed to benzene.

We investigated associations between benzene exposure and alterations of proteins and cells of the immune system among workers maintaining cargo tanks containing crude oil residues. Individual exposure to benzene, benzene in blood and urine, peripheral blood lymphocytes (total lymphocytes, lymphocytes in subpopulations CD3, CD4, CD8, CD19, CD56 and CD4/CD8 ratio), complement factors C3 and C4 and serum concentration of immunoglobulins (IgG, IgA, IgM and IgE) were analysed among 13 tank workers and nine unexposed referents (catering section). Benzene exposure was measured during three consecutive 12-h work days. Blood and urine samples were collected pre-shift on the first day (baseline), post-shift on the third day, and pre-next shift on the following morning. The time spent in the cargo tank was logged. The individual geometric mean benzene exposure in the breathing zone of tank workers over 3 days was 0.15 p.p.m. (range 0.01-0.62 p.p.m.) (n = 26). The geometric mean benzene concentration in blood post-shift was 12.3 nmol/l among tank workers versus 0.7 nmol/l among the referents. Tank workers showed a decline (versus referents) in IgM from baseline to post-shift (t-test, P = 0.04) and IgA from baseline to pre-next shift (t-test, P = 0.01). They also showed a decline in CD4 T cells from baseline to post-shift (t-test, P = 0.04). Suppression correlated with benzene exposure, benzene concentrations in blood and urine and time spent in the tank. The groups did not differ significantly in the change in other immune parameters. The clinical significance is unknown and warrants further studies.

Benzene exposure on a crude oil production vessel.

OBJECTIVES: The aim was to describe the personal exposure to benzene on a typical crude oil production vessel and to identify factors influencing the exposure level. METHODS: The study population included process operators, deck workers, mechanics and contractors on a production vessel in the Norwegian sector of the North Sea. The personal exposure to benzene during ordinary activity, during a short shutdown and during tank work was monitored using organic vapour passive dosimeter badges (3M 3500). Information on the tasks performed on the day of sampling was recorded. Exposure was assessed by grouping the measurements according to job category, mode of operation and the tasks performed on the sampling day. Univariate analysis of variance was used to test the differences between the groups. RESULTS: Forty-two workers participated in the exposure assessment, comprising a total of 139 measurements. The arithmetic and geometric mean of benzene exposure for all measurements was 0.43 and 0.02 p.p.m., respectively. Twenty-five measurements (18%) were below the limit of detection (0.001 p.p.m.), while ten samples (7%) exceeded the occupational exposure limit of 0.6 p.p.m. The geometric mean exposure was 0.004 p.p.m. (95% CI 0.003-0.006) during ordinary activity, 0.01 p.p.m. (95% CI 0.005-0.02) during shutdown and 0.28 p.p.m. (95% CI 0.16-0.49) during tank work. Workers performing annual cleaning and maintenance of tanks containing crude oil or residues of crude oil had higher levels of exposure than workers performing other tasks, including work near open hydrocarbon-transport systems (all P < 0.001). However, because of the mandatory use of respirators, the actual personal benzene exposure was lower. The job categories explained only 5% of the variance in exposure, whereas grouping by mode of operation explained 54% of the variance and grouping by task 68%. CONCLUSION: The results show that, although benzene exposure during ordinary and high activity seems to be low in the processing area on the production vessel, cleaning of tanks and performing maintenance work in a cleaned tank have a potential for high exposure.

Exposure to organic solvents during cosmetic finishing of cars.

The objectives of this study were to assess the exposure to organic solvents during degreasing, washing and polishing of cars, and to obtain information about acute health symptoms in car-finishing workers. Fifteen car shops participated in this study, and at these locations 36 workers had car finishing as their main working task. All 36 car-finishing workers and 17 randomly selected office workers from six of these car shops completed questionnaires on acute health symptoms. Personal monitoring of exposure to organic solvents was carried out in three representative shops. The highest exposure levels were found during degreasing of new cars, the median level of aliphatic hydrocarbons (C9-C13) being 22 p.p.m. (range 7-215 p.p.m.). This exposure level represents 50% (range 20-540%) of the Norwegian 8 h limit value for additive factor for these compounds. Only 28% of the workers used gas respirators regularly during this process. Very low exposure levels were detected during washing of second-hand cars and during polishing processes. The present study shows that car-finishing workers are exposed to high levels of organic solvents only for short periods of time. It seems that they are not adequately protected during these periods. However, the presence of acute symptoms was low, i.e. comparable to the prevalences in the reference group.

Activity profiles of the occupational health services in a multinational company.

The management of the European division of a multinational company was aware of possible differences in the occupational health services (OHS) at their different locations. The objective of this study was to carry out a baseline assessment of these OHS. Structured interviews with representatives of the OHS were conducted at 20 locations in 11 countries. The OHS Recommendation from the International Labour Organization (ILO) was used as a standard for the organization and functions of the OHS. Considerable differences in the activity profiles of the OHS were detected. The inter-enterprise, multidisciplinary OHS spent most of their time on surveillance of workers' health in relation to work and on preventive activities in the working environment. Little time was spent on curative services for individual workers. OHS made up of individual physicians and nurses generally spent much of their time on treatment of occupational and non-occupational diseases. This study has clarified the status of the OHS providers and the potential for improvements in order to meet the needs of the company's locations and to comply more closely with the ILO recommendation.

[Skin reaction after St Lucia holiday celebration]. / Hudreaksjon etter luciafeiring.

A 37-year-old man developed contact dermatitis on the front head after being exposed to dripping candles. The candles were placed in a crown on his head as he played St. Lucia in the traditional Lucia Day (13th December) pageant, trying to entertain the administrative staff of the University of Bergen where he was employed. Afterwards he washed his head with a soap he normally did not use. Probably the contact dermatitis is a skin reaction to the soap, but it is difficult to say whether the reaction was irritative or allergic. A similar case has not been reported earlier. It is of importance that noone stops celebrating the Lucia Day. However, proper precautions must be taken, with routines for avoiding exposure to stearine or unfamiliar soaps on the head of Lucia.

Vasodilation by calcitonin gene-related peptide (CGRP) and by transmural stimulation of the methoxamine-contracted rat hepatic artery after pretreatment with guanethidine.

Non-cholinergic, non-adrenergic vasodilation has been studied by transmural field stimulation of the isolated rat hepatic artery and compared with responses in the splenic artery. In the hepatic artery with rubbed endothelium, transmural stimulation caused a contracture that was blocked by phentolamine and potentiated after capsaicin. After pretreatment with guanethidine in order to deplete the neuronal stores of noradrenaline, the methoxamine-contracted hepatic artery was significantly relaxed by transmural stimulation; more efficiently than the splenic artery. This relaxation of the hepatic artery was attenuated following a 30 min exposure to capsaicin and largely blocked by tetrodotoxin (TTX). The relaxation by exogenous CGRP was independent of a functional endothelium. In contrast, vasodilation by substance P (SP) and neurokinin A (NKA), was completely dependent on an intact endothelium. Exogenous CGRP caused a near-complete relaxation of the methoxamine-contracted hepatic artery both before and after capsaicin treatment. CGRP was a more efficient relaxant of the hepatic than the splenic artery. These findings show that responses to transmural stimulation of the hepatic artery are modulated after pretreatment with capsaicin, indicating release of relaxing substances such as CGRP, presumably from capsaicin-sensitive neuronal stores. In conclusion, CGRP is a likely mediator of neuronal vasodilation in the rat liver, independent of the state of the endothelium.

Inhibition by VIP and atriopeptin II on the field stimulation evoked release of [3H]noradrenaline in the rat portal vein.

The modulatory effects of vasodilatory peptides on noradrenaline release from sympathetic nerve terminals have been studied in the rat portal vein model. Transmural field stimulation of the longitudinally mounted vein preparation evoked concomitant increases in the [3H]noradrenaline overflow and the integrated tension. Both responses were abolished by guanethidine or tetrodotoxin, whereas only the tension response was blocked by phentolamine. CGRP and VIP, both being present in intramural nerve fibers in the rat portal vein, were compared with atriopeptin II for modulatory effects. CGRP (100 nM) had no effect on the overflow of [3H]noradrenaline or the integrated tension response to transmural stimulation. VIP (30 nM) and atriopeptin II (30 nM) both caused significant reductions of both [3H]noradrenaline overflow and the integrated tension. These results indicate that the decreased tension response to transmural stimulation in the presence of VIP or AP II reflects the sum of both pre- and postsynaptic inhibitions.

Effects of calcitonin gene-related peptide (CGRP) on regional haemodynamics and on selected hepato-splanchnic arteries from the rat: a comparison with VIP and atriopeptin II.

The neuropeptides calcitonin gene-related peptide (CGRP) and vasoactive intestinal peptide (VIP) were compared with atriopeptin II (AP II) for vasodilatory responses in the rat. The haemodynamic changes following intravenous infusion of non-hypotensive doses were measured by the microsphere technique. Isolated segments of arteries from the hepato-splanchnic region were assayed for tension responses. CGRP (2.9 pmol kg-1 min-1) caused significant reductions in vascular resistances in the spleen, the stomach and the myocardium. VIP was without detectable effects at a similar dose. At a 10-times higher dose, AP II was still without hypotensive effect and vascular resistance was reduced only in the submaxillary gland. CGRP, VIP and AP II produced endothelium-independent relaxations of isolated segments of the left gastric artery, the splenic artery and the hepatic artery. In the superior mesenteric artery (SMA) the response to CGRP was reduced by 90% after the endothelium was disrupted. When a functional endothelium was present, the potencies for CGRP were higher in the gastric artery, the splenic artery and the SMA than in the hepatic artery. The orders of potencies for the peptides were, for the gastric artery and the SMA CGRP greater than AP II greater than VIP, and for the splenic artery and the hepatic artery CGRP = AP II greater than VIP. In conclusion, vasodilations in the spleen and the stomach occurred only in response to infusion of CGRP. Consistently, significantly higher potency values were found for CGRP than for VIP in isolated arteries from these organs. However, there were examples of discrepancies between the in vitro and the in vivo responses to CGRP and AP II.

Differential patterns of relaxation by synthetic atrial peptide (APII) in the pulmonary artery, ascending and distal abdominal aorta.

The vasodilatory effects of the synthetic rat atriopeptin (APII) have been studied in vitro in agonist-contracted, endothelium-denuded segments of the rat pulmonary artery, the ascending, and the distal abdominal aorta. In the pulmonary artery the contractures to methoxamine were inhibited more potently by APII (pD2 = 9.10 +/- 0.40, n = 6) than by the vasodilatory neuropeptide VIP (pD2 = 7.37 +/- 0.66, n = 6). The intrinsic activity of APII was 0.46 +/- 0.16 (n = 6). In segments previously exposed to either VIP or the beta 2-agonist salbutamol, APII was a near complete agonist (alpha = 0.82 +/- 0.17, n = 7 and 0.84 +/- 0.14, n = 6, respectively) without significant changes in the potencies. APII was a complete agonist also for the inhibition of the alpha-agonist-contracted segments of the aorta, however, with potencies 10-fold lower than in the pulmonary artery. VIP was without functionally significant effects in the aorta. The tachykinins (CGRP, SP, Neurokinins A and B) were without effects in all segments tested. In the ascending aorta, APII induced a long-lasting tachyphylaxis to the alpha-agonists, nearly completely abolishing the subsequent responsiveness to NA and methoxamine for more than 4 h.

Comparison of atriopeptins II and III, VIP and beta 2-adrenoceptor-evoked relaxations of the two layers of smooth muscle in the rat portal vein.

The relative importance of vascular relaxations induced by atriopeptins (AP), the beta-adrenoceptor agonist isoprenaline and of the neuropeptide VIP was studied in vitro on circular and longitudinal preparations of the rat portal vein. Two members of the rat atriopeptins (AP II and III) were equipotent with respect to relaxation of the spontaneously contracting outer, longitudinal layer and of the alpha 1-contracted inner, circular layer. The potency for AP II was about 13 times lower in the inner (pD2 = 7.48 +/- 0.73, n = 6) than in the outer layer (pD2 = 8.60 +/- 0.34, n = 6). No significant difference was apparent between the intrinsic activities for AP II in the two layers. The potencies for AP II were for both layers higher than those for VIP while the intrinsic activities for AP II were significantly lower than for VIP and for the reference agonist, isoprenaline in both layers. Atriopeptin II was equally efficient in relaxing the K+-depolarized and alpha 1-contracted longitudinal segments. Neither the beta-antagonist, propranolol nor the guanylate cyclase inhibitor, methylene blue, modified the potency or the intrinsic activity of AP II. These results suggest that concentrations of circulating atriopeptins above 10 nM may contribute to reduction of vascular tone by the methylene blue insensitive receptors for AP II and III in the portal-mesenteric vein region.

VIP inhibition of vascular smooth muscle: complementary to beta 2-adrenoceptor mediated relaxation in the isolated rat portal vein.

Exogenous VIP caused a concentration dependent inhibition of the spontaneous mechanical activity in the isolated rat mesenteric-portal vein preparation via a mechanism which was completely independent of the propranolol-blocked beta-adrenoceptor, of high K+ in the medium and of exogenous bovine pancreatic polypeptide, neurotensin and opioids. The potency of VIP (pD2 = 7.52 +/- 0.18, n = 6) was about 30 times higher than that of isoprenaline in the atropine and phentolamine-blocked preparation. The isoprenaline inhibition was mediated via a beta 2-type of adrenoceptor with low apparent affinity for noradrenaline (intrinsic activity (alpha) = 0.27 +/- 0.01, n = 8). Opposite effects of exogenous VIP and noradrenaline were on the other hand observed in the atropinized and beta-blocked preparation. These results suggest that in the rat portal vein neuronal VIP and circulating adrenaline may be complementary in their antagonism of the alpha-adrenoceptor mediated increase in contractility.