Search

Objectives: In 2011 recommendations for the prescription of lung cancer in coke oven workers were made in the UK. In the 1970s, a powered helmet respirator, the Airstream helmet, was introduced to the UK coking industry with the aim of reducing exposure to polycyclic aromatic hydrocarbons (PAH) aerosols and consequent lung cancer risks for workers on the coke oven tops. This review set out to identify the level of protection afforded by the Airstream helmet, when the helmets could be considered to have provided effective protection and whether the levels of protection have been maintained to the current time. Methods: Five approaches were taken to identify review material, including searching the peer-reviewed and grey literature; searching material held in the National Archive; using a Freedom of Information to the Health and Safety Executive; interviews with employees involved in the introduction of the Airstream helmet; and acquisition of company reports. Results: The two principal companies involved in coke production in the UK took different approaches to the introduction of the Airstream helmets. Because of this, it can only be considered that effective wearing occurred in the industry as a whole from 1982 onwards. Exposure measurements made by British Steel in the late 1970s suggested that the mean protection factor of the Airstream helmet was ~10 (5th percentile ~2.5), regardless of whether exposure was assessed as the inhalable aerosol or other measures more specific to aerosol of PAH. More recent data collected using biological monitoring has identified that average urinary levels of 1-hydroxypyrene (1-HP) generally correspond with the inhalation occupational exposure limit for benzene soluble material. Although on occasions, relatively high air concentrations in-mask and urinary 1-HP concentrations have been identified, underlining the necessity to maintain close supervision of workers wearing respirators. Conclusions: Overall, we concluded that the wearing of helmet respirators has effectively controlled long-term average exposure to PAH for most workers on coke ovens since 1982. [ABSTRACT FROM PUBLISHER]

The International Agency for Research on Cancer controversially has classified formaldehyde as causing nasopharyngeal carcinoma and myeloid leukemia. To provide further information on this question, we extended follow-up of a cohort of 14,008 chemical workers at 6 factories in England and Wales, covering the period 1941–2012. Mortality was compared with national death rates for England and Wales, and associations with incident upper airway cancer and leukemia were explored in nested case-control analyses. We observed excess deaths from cancers of the esophagus (100 observed vs. 93.1 expected), stomach (182 vs. 141.4), rectum (107 vs. 86.8), liver (35 vs. 26.9), and lung (813 vs. 645.8), but none of these tumors exhibited a clear exposure-response relationship. Nested case-control analyses of 115 men with upper airway cancer (including 1 nasopharyngeal cancer), 92 men with leukemia, and 45 men with myeloid leukemia indicated no elevations of risk in the highest exposure category (high exposure for ≥1 year). When the 2 highest exposure categories were combined, the odds ratio for myeloid leukemia was 1.26 (95% confidence interval: 0.39, 4.08). Our results provide no support for an increased hazard of myeloid leukemia, nasopharyngeal carcinoma, or other upper airway tumors from formaldehyde exposure. These results indicate that any excess risk of these cancers, even from relatively high exposures, is at most small. [ABSTRACT FROM PUBLISHER]