Evaluating Risks of Acquired Clinical Vulnerability Among Subjects Exposed to E-Waste - Reviews of Environmental Contamination and Toxicology - page 10

These confounding factors include the following: environmental pollutants
emanating from industry or trafic, or concurrent exposure to occupational haz-
ards, indoor air pollutants, tobacco smoke, alcohol, prescription drugs, and recre-
ational drugs. There were more than 20 hypothesis-generating studies, but the
results were inconsistent. Some studies showed associations between landills and
various health impacts, while other studies reported no associations. The strongest
suggestion for causality was generated by studies having to do with reproductive
outcomes, such as reduced birth weight or some birth defects. However, all studies
lacked direct exposure assessment, and the limited sample sizes of most studies
made a more speciic analysis impossible.
Considering all the uncertainties, it is concluded that the data available on land-
ills and their risks to humans strengthens the suspicion that exposure to emissions
from hazardous wastes do pose a risk of ill health to some exposed individuals.
However, existing data do not substantiate with suficient evidence to indicate which
landills, or what exists in them, are the primary culprits that may be responsible for
the observed small increases in risk (WHO 1998 ).

3.2 Hazards Associated with Disposal by Incineration

A search for published reports on incineration of E-waste yielded (Saffron et al.
2003 ) 50 primary studies and three reviews. The majority were studies on com-
munities, although there were also 14 occupational health studies, in which a wide
array of health outcomes were investigated: e.g., cancer (15 studies), health prob-
lems/diseases/unspeciied health effects (12 studies), biomarkers (10 studies),
reproductive outcomes/developmental effects on children (9 studies), symptoms
(8 studies), mortality (5 studies), injuries/poisoning (3 studies), psychosocial
impacts (2 studies), economic impacts (1 study). Among the occupational health
studies, there were three in which exposure was presumed because of worker
occupation at the site of the incineration, two studies that utilized quantiied ambi-
ent measurements of particulate matter (with an aerodynamic diameter £10 mm
(PM 10 )) or metals, and seven studies that provided quantiied personal measure-
ments (of BLLs or of urinary mutagens). Among the studies in which communi-
ties had residents living near incinerators, four used quantiied ambient
measurements, two used quantiied estimates, and 27 used residence alone as a
proxy for exposure. Furthermore, there were four hypothesis-testing studies
(Bresnitz et al. 1992 ; Shy et al. 1995 ; Lee and Shy 1999 ; Gray et al. 1994 ). Lee
and Shy ( 1999 ) analyzed how health outcomes varied according to the degree of
exposure to ambient pollutants, as well as to other cofactors including, sex, age,
respiratory hypersensitivity, period of time spent outdoors within the area of the
selected community, and surrogate measures for indoor air pollution exposure
(vacuum use and experience of air irritants at work). The four hypothesis-testing
studies consistently showed no association between the hazards from incineration
and any health outcomes.