I am a science nerd and always have been. Just this week I got
real excited by ”Harvesting therapeutic proteins from animal
slobber” in this week’s (2/22/2017)
Chemical & Engineering News, just as I was about “Slow-release nitrogen fertilizer could
increase crop yields: A new nanoparticle-based fertilizer…” in the same issue. I spend several hours a week updating my
EndNote database, where I have catalogued over 3,000 science journal articles.
I received my tee-shirt this week: March for Science – Earth Day 2017. I occasionally, for fun, visit the National
Center for Emerging and Zoonotic Infectious Diseases (NCEZID) just to catch up. I jump at the chance to encourage people
to listen to The Great Courses audio lecture series Earth's Changing Climate.
I take science seriously, which explains my annoyance at seeing
the negative news clipping below and receiving word that David L Lewis is
again pretending to be an honest whistleblower scientist fired by the US EPA
over his opposition to Part 503 regulations. Apparently a new documentary
is in the works featuring Lewis as a hero: How EPA Faked the Entire Science of Sewage
Sludge Safety: A Whistleblower’s Story. It was just in January that I started out a newsletter
noting that "David Lewis, long-retired from EPA but not from
anti-biosolids activism, has posted to the United Sludge Free Alliance his 'recommendation for a new EPA Clean Soil
Standard'.” And this
week I learned that Caroline Snyder has been stirring up folks in eastern
Pennsylvania that there are no science articles showing biosolids is safe. THIS
IS NOT TRUE!
Lewis’s
argument of biosolids risk is absurd on its face. Virtually every state and
federal regulatory system accommodates and supports biosolids recycling; that
is hundreds of environmental regulators. Virtually every scientific article
finds positive attributes of biosolids use in soils; I have 600 such
references, authored by probably more than 1,500 scientists. The wastewater
profession backs this practice; WEF counts itself having 33,000 members. For DL Lewis to be on the right side of this
issue, these scientists, engineers, and regulators would need to be in some
sort of mass conspiracy. How can rational media reporters be so blind to this
absurdity?
The “fake news” story that is told around biosolids follows
common themes of mythology. A number of years ago, Pulitzer Prize winning
science writer Jon Franklin explored this theme in “Biosolids Hits the Fan” presentation to the opening general session the last time
the national biosolids conference was held in the Seattle vicinity.
This argument has also been provided a veneer of respectability
by several journal articles, now over a decade ago. Lewis made that case in Interactions of pathogens and irritant
chemicals in land-applied sewage sludges (biosolids). He speculated that “an increased risk of infection may
occur when allergic and non-allergic reactions to endotoxins and other chemical
components irritate skin and mucus membranes and thereby compromise normal
barriers to infection.”
Works
by other familiar anti-biosolids activists have appeared in technical journals.
Today’s most active activist, Carolyn Snyder, authored in 2005 for the
International Journal of Environmental and Occupational Health the article The Dirty Work of Promoting “Recycling” of
America's Sewage Sludge. Helane Shields
authored in 2003 for an online publication, NEW SOLUTIONS: A Journal of
Environmental and Occupational Health Policy, an ominously titled article Sludge Victims: Voices from the Field. And in that same year and in the same publication, a
more extensive treatment of the claims of biosolids-related illness was set
forth by Cornell Waste Management Institute’s Ellen Z Harrison, Investigation of Alleged Health Incidents
Associated with Land Application of Sewage Sludges: “Residents near land application sites report illness.
Symptoms of more than 328 people involved in 39 incidents in 15 states are
described.” A journal article with a theme linking biosolids use to
environmental justice is Public Officials’ Perspectives on Tracking and
Investigating Symptoms Reported Near Sewage Sludge Land Application Sites. The
authors of this paper observed: “Residents living close to treated farmland
have reported becoming ill following land application of sludge. No systematic
tracking or investigation of these reports or of land application practices
that could affect off-site migration of chemical and biological constituents of
the sludge has occurred, however.”
These
“science” articles share the specific feature that neighbors to land
application sites are self-reporting symptoms of ill health. This is not
medical science. Medical science is founded on objective measurements and
on plausible mechanisms linking pathogens or toxins to health effects. These
standards of medical science are not met with self-reported illnesses.
Nevertheless,
WERF (now WE&RF) actively responded to these wide-spread and persistent
public concerns. It sponsored research leading to the 2005 report. Health Effects of Biosolids Odors: A
Literature Review and Analysis. This
review was followed by WERF’s more proactive Epidemiologic
Surveillance and Investigation of Illness Reported by Neighbors
of Biosolids Land Application Sites, Phase 1,
“a draft protocol designed to be used by local, state, and federal health and
environmental officials,” and by Pilot Testing: Surveillance and Investigation
of the Illness Reported by Neighbors of Biosolids Land Application and Other
Soil Amendments, which tested the protocol. This project had its bumps
in the road, in part because the Phase 1 authors were in disagreement with the
focus and findings as they were shaped by the project review team. One
underlying issue is this: are people who believe they have been sickened by
biosolids exposure in fact experiencing ill health?
I
took a shot at the issue of whether, in the absence of pathogen and toxicant
exposures, can biosolids make people sick? I had been put on to this topic by
Dr. William Cain, the principal investigator of WERF”s first report on health
effects, in a visit to his odor lab shortly after his WERF report was complete.
He explained that the chemical sensing system, particularly the trigeminal nerves in the nose, could be triggered by biosolids odors and that
odor triggers could cause physical reactions, even subconscious ones. After a
long, circuitous path of journal reading, I set this argument down in 2007 in Biosolids Odorant Emissions as a Cause of
Somatic Disease: What Ought to be Our Profession’s Response? I convinced myself that we, as environmental
professionals, ignore odor complaints at our peril. My basic argument is that
we can reasonably predict that someone in a community affected by biosolids
odors may become fearful and experience physical manifestations of panic
arising from odors, not pathogens.
Over the past ten years, scientific
tools for investigating pathogens and exposures are increasingly sensitive and
affordable. Has science raised the level of concerns with biosolids-borne
toxicants and pathogens? The short answer is no.
But we do now know a lot more about
biosolids-borne microbes. A series of reports were issued by Dr. Jordan
Peccia’s lab at Yale University. He and his grad students looked far
beyond our traditional, regulation-inspired indicator organisms. In Toward a consensus view on the infectious risks associated with
land application of sewage sludge he
concluded “such analysis demonstrates that the tradition of monitoring pathogen
quality by Salmonella spp. and enterovirus content underestimates the
infectious risk to the public…” In Source tracking aerosols released from land-applied class B
biosolids during high-wind events,
Peccia’s team concluded that “[T]he
application of DNA-based source tracking to aerosol samples has confirmed that
wind is a possible mechanism for the aerosolization and off-site transport of land-applied
biosolids." Further, in Prevalence of Respiratory Adenovirus Species B
and C in Sewage Sludge, the
researchers asserted “[T]hese findings reinforce
the necessity to consider aerosol exposure to sewage-derived pathogens."
But, in terms of actual risk, the evidence seemed to point to exposures not
being of great health concern. In Respiratory Toxicity and Inflammatory Response in Human
Bronchial Epithelial Cells Exposed to Biosolids, Animal Manure, and
Agricultural Soil Particulate Matter the
article “…suggests that an
inflammatory aerosol exposure in the TB region could only occur under worst
case scenarios…,” which seems relatively benign.
The other major team looking at the
microbial content of biosolids and its implication for worker and community
health is at the University of Arizona, that of Drs. Ian Pepper and Chuck
Gerba. This team put out the report Pathogens and Indicators in United States
Class B Biosolids: National and Historic Distributions, a “major
study of the incidence of indicator organisms and pathogens found within Class
B biosolids
within 21 samplings from 18 wastewater treatment plants across the United
States….illustrating that the Part 503 Rule has been effective in
reducing public exposure to pathogens relative to 17 yr ago.” As with the
Yale work, this team’s graduate students studied Bioaerosol transport modeling and risk
assessment in relation to biosolid placement,
concluding that for nearby residents “little risk of infection from
aerosolized bacteria and at no risk from aerosolized viruses.” This works was
also reported and confirmed in Estimation
of bioaerosol risk of infection to residents adjacent to a land applied
biosolids site using an empirically derived transport model. When the new assessment tool, QMRA, or quantitative
microbial risk assessment, was applied to manures and biosolids, in Land Application of Manure and Class B
Biosolids: An Occupational and Public Quantitative Microbial Risk Assessment, the researchers showed that “decreases in risk were
typically over six orders of magnitude beyond 30 d. Nearly all risks were
reduced to below 10−4 when using a 4-mo harvest delay for crop
consumption.” These confirmed the effectiveness of Part 503 management
regulations.
What can we say
today with these new tools, new studies, new technologies, and new complaints?
We still can confidently say that biosolids land application has not proved a
significant source of pathogens that cause sickness in workers and communities.
This is good, but not sufficient. Odors still provoke panic-related symptoms,
so we need to continue our search for improved odor qualities. We should not be
shy about offering to respond to claims of ill health effects of biosolids,
because some of these reports arise from genuine fears. Class A pathogen
treatment vastly reduces risks compared to Class B treatment, so our industry’s
move to Class A is wise. Land management practices that prevent windblown dust,
incidentally also reducing odorant releases, are always smart.
We know
biosolids is safe, but our public does not. We need to go beyond our rational
brain and toward our emotional nature, our heart, and follow our nose. Even the
safest biosolids by any other name is Still Not a Rose.
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