world cancer report - iarc

Agent Cancer site/cancer
IARC Group 1
Aflatoxins Liver
Chronic infection with hepatitis B virus Liver
Chronic infection with hepatitis C virus Liver
Erionite Lung, pleura
Radon and its decay products Lung
Solar radiation Skin
Environmental tobacco smoke Lung
IARC Group 2A
Diesel engine exhaust Lung, bladder
Ultraviolet radiation A Skin
Ultraviolet radiation B Skin
Ultraviolet radiation C Skin
Table 2.10 Agents and mixtures which occur mainly in the general environment but to which exposure
may also occur in an occupational context.
A worldwide problem
Evidence on occupational cancer has
been obtained mainly in developed countries.
To a large extent, the critical data
concern the effects of high exposure levels
as a consequence of industrial practice
during the first half of the 20th century.
Few studies have been conducted in
developing countries, other than some in
China. Since the period, twenty to thirty
years ago, to which most studies pertain,
there have been major changes in the
geographical distribution of industrial
production. These have involved extensive
transfer of technology, sometimes
obsolete, from highly-industrialized countries
to developing countries in South
America and in Asia. For example, the
manufacture of asbestos-based products
is relocating to countries such as Brazil,
India, Pakistan and the Republic of Korea,
where health and safety standards and
requirements may not be so stringent
(Reduction of occupational and environmental
exposures, p135). Occupational
exposures to carcinogenic environments
are increasing in developing countries as
a result of transfers of hazardous industries
and the establishment of new local
industries as part of a rapid global
process of industrialization [8].
A particular problem in developing countries
is that much industrial activity takes
place in multiple small-scale operations.
These small industries are often characterized
by old machinery, unsafe buildings,
employees with minimal training and
education and employers with limited
financial resources. Protective clothing,
respirators, gloves and other safety
equipment are seldom available or used.
The small operations tend to be geographically
scattered and inaccessible to
inspections by health and safety enforcement
agencies. Although precise data are
lacking, the greatest impact of occupational
carcinogens in developing countries
is likely to be in the less organized
sectors of the relevant industries.
Examples include the use of asbestos in
building construction, exposure to crystalline
silica in mining and mining construction,
and the occurrence of polycyclic
aromatic hydrocarbons and heavy
metals in small-scale metal workshops
and in mechanical repair shops.
The most generally accepted estimates
of the proportion of cancers attributable
Fig. 2.19 Asphalt road-workers (shown here in
India) are exposed to polycyclic aromatic hydrocarbons.
Fig. 2.20 In modern mines (such as those of
Charbonnages de France), the prevention of occupational
risk is a major concern, which is being
addressed on both collective (reduction of dust,
organization of transport) and individual (use of
suitable protection equipment) levels.
Fig. 2.21 Textile dyeing in Ahmedabad, India.
Protection against occupational exposures is
often suboptimal in developing countries.
Occupational exposures 37