Protecting Workers from Ultraviolet Radiation - icnirp

Protecting Workers from Ultraviolet Radiation
discharge lamp may continue to operate and severe over exposure of the eye and skin can occur.
Normally roadway lamps are enclosed in impact resistant covers (polycarbonate) which totally
absorb any hazardous short-wavelength UVR. Workers who replace lamps in high bay areas
such as sporting halls, air craft hangers and large industrial buildings must be trained to identify
damage lamps and their safe replacement.
6. Health Risk Assessment from Human Studies
6.1 Skin Cancer Studies
A number of studies of the quantitative risk of skin cancers (Gallagher 1985, 2005) in outdoor
workers have been carried out in recent decades.
There is strong evidence from numerous epidemiological sources that excessive cumulative
exposure to solar radiation causes squamous cell cancer of the skin (SCC) and lip cancer
(AGNIR 2002). There is also evidence that sun exposure is related to the risk of basal cell
carcinoma (BCC), although the pattern of exposure that is responsible is less clear; there is
evidence that intermittent recreation exposure may be important as well as evidence for an effect
of cumulative exposure. Traditionally, non-melanoma skin cancer (NMSC) has been considered
a tumor typically seen in elderly, male farmers, but in epidemiological data although some
routine studies show non-melanoma skin cancer to be more common in outdoor than indoor
workers, this has not always been found. A possible explanation comes from a study of SCC and
BCC in Queensland (Green et al 1990), in which it was found that people with fair or medium
complexions and with a tendency to sunburn are under-represented amongst outdoor workers,
suggesting that there may be self-selection of sun- tolerant individuals (i.e. people with low risk
of NMSC) to become and remain outdoor workers. Furthermore, this study found that outdoor
workers were more likely than others to wear sunhats, raising the possibility that they employ
more sun protection, on average, than other individuals. Thus, although there is good evidence
that excessive outdoor sun exposure over long periods will increase the risk of NMSC, it is not
necessarily the case that outdoor workers are those with the highest risks of these tumors.
Cutaneous malignant melanomas (CMMs) are responsible for 80% of skin cancer deaths (WHO
2003) even though CMMs represent only 5% of the skin cancer cases. Solar exposure is an
important aetiology of cutaneous melanoma although the causal solar exposure patterns are less
clear. Both intermittent recreational exposure of untanned skin and cumulative exposures are
aetiological factors for cutaneous melanoma.
As for indoor workers, analyses of data from large studies have generally found greater risk of
melanoma in indoor than outdoor occupations (according with the intermittent exposure
hypothesis of aetiology), although the reverse has been found for head and neck melanoma. In
individual-based studies, results on outdoor versus indoor workers have been less consistent.
The evidence of the causal role of UVR in melanoma has been recently strengthened by studies
of subjects who routinely engage in artificial UVR tanning. (Swerdlow and Weinstock 1998,
Veierod et al 2003, Gallagher et al 2005).
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