Geoscience Reference
In-Depth Information
effects. However, Clark et al. (
1984
) reported no differences in illness rates and no
isolation of viruses or bacteria.
While studies of WWTP workers and sewage plant workers suggest or document
some health effects that may be related to exposure to sewage and/or biosolids,
those of biosolids applicators vary. Tanner et al. (
2008
) estimated occupational risks
through the collection of microorganism levels in air immediately downwind of land
application operations. Risks from aerosolized microorganisms at biosolids land
application sites were lower compared to wastewater treatment plants. Robinson
et al. (
2006
) developed and performed a pilot test of a health survey for WWTP
workers, and although eight reported at least one potentially associated symptom,
personal protective equipment (gloves, goggles, respirators) were not always worn
to protect from potential exposure. Workers associated with biosolids land appli-
cation activities were interviewed in a study by Burton and Trout (
1999
) and all
five had reported at least one instance of gastrointestinal illness after working with
biosolids at the WWTP or during application, while four of the five reported at
least one symptom of various gastrointestinal symptoms or repeated intermittent
headache. However, the site in question did not comply with EPA regulations, and
at times before the study, had applied biosolids that exceeded the EPA fecal coliform
upper limit for Class B biosolids (NIOSH
2002
).
Community exposure to biosolids has been evaluated, although findings indi-
cate further study is needed. Dorn et al. (
1985
) performed a 3-year prospective
epidemiologic study in three geographic areas of Ohio on families of biosolids
receiving farms and control farms. No significant differences were found in gen-
eral symptoms or digestive or respiratory illness between the families. Lewis et al.
(
2002
) surveyed 48 residents in eight states reportedly affected by ten biosolids land
application sites although no control group was included. Results indicated at least
25% of participants reported coughing, burning throat or burning eyes within 1-h of
exposure.
10.4 Methodology
In 2004, researchers from the University of Toledo and Bowling Green State
University along with collaborators from Central State University, Kent State
Unviersity, Cleveland State University, Youngstown State Univeristy, the University
of Michigan, Oregon, Ohio WWTP and Bowling Green, Ohio WWTP developed
a project to evaluate potential impacts of land application of Class B biosolids on
human health using a geographic information system (GIS
)
. This ongoing project is
very comprehensive and seeks to analyze the potential pathways in which pathogens
and heavy metals, through aerosols and transport of contaminants in runoff away
from application fields, could result in human exposures and cause associated
health problems. Field observations and modeling were utilized to investigate the
fate of pathogens, heavy metals and pharmaceutical and personal care products
(PPCPs) and the pathways of these constituents off of the fields. We have identified
