Arctic stratospheric ozone depletion and increased UVB radiation: potential impacts to human health

Abstract

Contrary to popular belief, stratospheric ozone depletion, and the resultant increase in solar UV-B (280-320 nm), are unlikely to fully recover soon. Notwithstanding the success of the Montreal Protocol in reducing the amount of ozone destroying chemicals into the stratosphere, the lifetimes of these compounds are such that even with full compliance with the Protocol by all countries, it will be decades before stratospheric ozone could return to pre-1980 levels. This raises the question, therefore, of what will happen to biological processes essential to the maintenance of life on earth which are sensitive to damage by increased UV-B radiation, particularly those involved with human health? The polar regions, because of the vagaries of climate and weather, are the bellwether for stratospheric ozone depletion and will, therefore, be the first to experience impacts due to increases in solar UV-B radiation. The impacts of these are incompletely understood and cannot be predicted with certainty. While some UV-B impacts on human health are recognized, much is unknown, unclear and uncertain. Thus, this paper attempts, as a first approximation, to point out potential impacts to the health and welfare of human inhabitants of the Arctic due to increased solar UV-B radiation associated with stratospheric ozone depletion. As will be seen, much more data is critically needed before adequate risk assessment can occur.

Melanoma induction by ultraviolet A but not ultraviolet B radiation requires melanin pigment

“…Here we confirm the importance of ultraviolet B in melanoma, particularly significant in view of the increasing melanoma incidence rates and the potential health effects50 of global increases in ultraviolet B directly associated with stratospheric ozone depletion over highly populated latitudes51. We further provide evidence for a novel and important role of ultraviolet A in concert with melanin in melanoma and thus provide an experimental explanation for the observations that artificial ultraviolet A tanning is a significant melanoma risk52 particularly in young women53.…”

Clinical risk factors for osteoporosis are common among elderly people in Nuuk, Greenland

“…Still, we included the question “limited sun exposure” in our questionnaire and we consider it to be a risk factor because the high intensity of the light in Greenland during spring and indication of dermal vitamin D production even in North Greenland (37) in addition to vitamin D provided by the traditional Inuit diet (38). Furthermore, stratospheric ozone depletion increases the UVB radiation in the circumpolar area in the range required for dermal vitamin D production (39). Thus, sun exposure is likely an issue in populations in Greenland too.…”

The Protective Role of Melanin Against UV Damage in Human Skin†

“…UVC (200–280 nm) does not reach the surface of the earth, as it is screened out by atmospheric oxygen and absorbed by the ozone layer. However, the penetration of UVB is enhanced by the increasing depletion of the ozone layer leading to a higher risk for UV‐induced carcinogenesis (2). It has been estimated that a 1% decrease in ozone increases melanoma mortality by 1–2% (3).…”