HEALTH EFFECTS

increase in antimicrobial resistance among isolates of Salmonella in the U. S. from
1967 to 1975>

HEALTH EFFECTS ASSOCIATED WITH WASTEWATER TREATMENT AND
DISPOSAL: N.E. KOWAL, H.R. PAHREN. U.S. ENVIRONMENTAL
PROTECTION AGENCY.  Published in the WEF's Journal Water
Pollution Control Federation (1981) vol 53 (6): pp.776-786

Lucas reviewed the nonmicrobiologic contaminates of
wastewater aersols, noting that toxic gases and myriad
chemicals, both organic and inorganic, may pose a significant
hazard to wastewater treatment workers and potentially to the
general public in surrounding areas.

Rylander and Lundholm investigated several clinical symptoms
among workers at wastewater treatment plants. Because there
were high levels of gram-negative bacteria and bacterial
endotoxins present in the wastewater plant environment, it
was suggested that the symptoms were caused by exposure to
airborne endotoxins.

Because of the concern that antibiotic resistance factors (R
plasmids) in coliforms are being transferred to enteric
bacterical pathogens in wastewater, environmental waters, or
individuals who harbor such coliforms previously ingested in
the course of water associated activities, some investigators
have suggested the need for more stringent water quality
standards limiting the densities of coliforms in enviromental
waters and for more advanced purfication of wastewater prior
to its discharge into the environment. To address this issue,
Shaw and Cabelli isolated multiple-drug-resistant strains of
Escherichia coli, representing about 8.3% of the total E.
coli population, from the water at an estuarine site, --


Bell et al examined the incidence of R factors (or Plasmids)
for antibiotic resistance in coliform, fecal coliform, and
Salmonella bacteria of the Red River in Canada. It was
calculated that the populations of fecal coliforms containing
R factors were as high as 1,400 per 100ml and that an
accidental intake of a few milliliters  of water could lead
to transient or parmanent  colonization of the digestive
tract.

These reports may be viewed in the context of recent
documentation of increase in antimicrobial restance among
isolates of Salmonella in the U. S. from 1967 to 1975>

For composting basic precautions were recommended:
prospective workers should be given physical examinations;
personnel with histories of allergic sensitivity; resent
renal or cardiac disease, or immunosuppressive therpy should
not be employed in composting opperations: front-end loaders
should be equiped with enclosed air conditioned cabs or
operators should wear dust filtering masks; and plants should
not be sited in the vicinty of hospitals and nursing homes.

Lundholm and Rylander described subjective symptoms (nausea,
headache, and diarrhea) among workers in an experimental
compost plant, resulting from airborne gram-negative bacteria
from household solid waste. The potential health effects of
exposure to microbil agents associated with the composting of
municipal wastewater sludge  were reviewed by Clark etal. Two
agents of particular concern were the fungus A. fumigatus,
and endotoxins, from large numberss of gram-negative bacteria
in sludge. The preliminary date on antibody response to the
compost workers at the Beltville-Blue Plains sites to
endotoxins suggest that to reduce exposure it may be
advisable to take reasonable precautions such as the use of
respirators by compost workers and periodic water spraying of
the compost sites to reduce dust.

LAND APPLICATION

Sagik et al. provided a comprehensive overview of the health
risks associated with bacteria and viruses in land
application of municipal sludge. In 1978, 32 outbreaks of
acute waterborne disease involving 11,435 cases were reported
to the Center for Disease Control (CDC) and EPA. Of those
outbreaks for which the etology was determined, Shigella
accounted for 4, Giardia lamblia for 4, parvovirus-like
agents for 3, Salmonella for 2, chemicals for 2, and
Campylobacter fetus subspecies jejuni for 1. Untreated ground
water was responsible for 10 outbreaks with 1,471 cases.

HEALTH effects associated with wastewater treatment,
disposal, and reuse. C.S. Clark. Published in WEF's Journal
Water Pollution Federation (1987) vol 59(6): pp 436-440

Hadeed reported that the wastewater industy has retained its
number one status as the most dangerous career field based on
the results of the 1986 Annual WPCF Safety Survey.

In New york, 164 workers from 14 wastewater plants work had a
higher frequency of uninary mutagens, after controlling for
smoking, than 72 water treatment workers in the same
municipalities. The authors stated that while these findings
provided strong evidence of increased exposure to mutagenic
substances among wastewater workers, the long-term health
effects of their exposure was unknown.

In a review of the literature on on the biological health
risks associated with wastewater and sludge handling and land
application, Block concluded that the literature on the
health effects of exposure to wastewater sludge on the health
of workers was scarce.

A review of serologic methods to determine infections from
exposure to wastewater and refuse concluded that four of the
five wastewater worker studies reviewed there was evidence
that exposure wastewater/sludge carried with it a slight risk
of viral infection, usually limited to those with the highest
exposure.

Jakubowshi reviewed 11 U.S. Environmental Protection Agency-
sponsered studies of the potential health effects associated
with the treatment and disposal of wastewater and wastewater
sludge. He concluded that although most of the evidence was
negative, the problems in quantifyinig exposure and the
absense of a clear endpoint for necessary effect must be
considered.

Fifteen outbreaks of cysticercosis in cattle related to
wastewater and sludge application on farmland in Denmark were
described and likely infection sources identified. Results of
two serologic surveys of Scottist cattle for ELISA antibodies
for taeniid parsites were presented by Sewell et al. and the
need for more specific diagnostic procedures to make testing
more usful was expressed.

Havelaar and Jones discussed various aspects of the
potentuial for salmonellosis resulting from agricultural use
of waste materials. Angus discussed several factors which
could reduce possible infections Cryptosporidium from the
land application of agricultural and domestic sludges.

In a discussion of epidemiological studies of wastewater
populations, the need for a health status survey of the
exposed population was stressed. A review of the infectious
risk ofsarcosporidia from irrigation was sludge revealed that
the risk was increased by the high resistence of Sarcocystis
spp. cysts to environmental conditions.

The potential role of wastewater and sludge in spreading
ascariasis in Europe, the efficiency of various treatment
techniques, and the need for surveillance programs was
reviewed by Pawlowski and Schultzberg. Watson reviewed the
potential health risk to humans and animals from bacteria,
helminths and viruses in sludges applied to land. Wekerle
presented a review of sludge as a vecter for transmission and
identified several research needs.

In a report on the domestic waste exclusion of hazardous
waste discharged to POTWs numerous case studies were referred
to which involved sewer maintenance workers who have been
injured or killed from hazardous gases formed in sewers.
Pollutant incident reports from 10 POTWs reflect occurences
of occupational health hazards were cited.

Melius cited some difficulties in designing medical
surveillance programs for hazardous waste workers because of
usual exposure to low levels of multiple contaminants and the
occasional exposure to potentially high levels