Sludge Watch ==> Small Town Ontario Sludge Tests - A Case for Precaution?

[maureen.reilly at sympatico.ca]

Small Town Ontario Sludge Tests--A Case For Precaution?

Urban centres all over the world have a major problem piling up. Every hour 
tonnes of toxic and pathogenic sewage sludge are being created that must be 
processed and disposed of safely. Rapidly filling landfills, along with the 
past environmental challenges and high cost of incineration, have led many 
municipalities to seek out other disposal options. Consequently, sludge has 
now become a lucrative business for waste disposal companies, offering it to 
farmers as "free" fertilizer. In Canada, selling it would in fact contravene 
the federal fertilizer legislation--designed to protect farmers from what 
else is in it. But this experiment in recycling--with what is in effect a 
hazardous waste--may come with a much higher price in future. It is now 
becoming well documented that ecosystems are being compromised and humans 
and wildlife are being harmed through this practice. In the U.S., the 
Cornell University Waste Management Institute have published a number of 
important reports, featuring major concerns about the impacts on human 
health from growing crops or grazing livestock on soil "conditioned" with 
sewage sludge.

The conundrum is that sewage sludge contains a complex matrix of contaminant 
ingredients that is far from just the "nutrients" needed for "soil 
conditioning". Urban sludge typically contains a chemical soup whose 
ingredients include: polychlorinated biphenyls (PCBs); chlorinated 
pesticides such as DDT, chlordane, lindane, 2,4-D; chlorinated compounds 
such as dioxins, polycyclic aromatic hydrocarbons (PAHs); heavy metals such 
as cadmium, lead and mercury (all known endocrine disrupters) and 
miscellaneous other substances including asbestos, petroleum products, 
surfactants and industrial solvents. Of equal concern are an assortment of 
harmful pathogens--including bacteria such as E-coli, shigella, salmonella 
and campylobacter; polio and hepatitis viruses; parasites like 
cryptosporidium and giardia; and fungi. An Ottawa University study found 
that 80% of viruses and a high percentage of bacteria and parasites survive 
the aerobic and anaerobic treatment process and are concentrated in the 
sludge. Because of the real and potential risks presented by farm sludging, 
reputable scientists are raising warning flags that are generating concern 
and unease.

In Canada, and especially the province of Ontario, concern about the 
potential dangers of sludge in rural communities soared after the water 
contamination tragedy in Walkerton and Justice Dennis O'Connor's conclusion 
that better controls are needed on farm pollution from all sources. And one 
of the most "fecally aware" communities is Prince Edward County--where this 
writer lives. After researching the subject for about six years, I am 
alarmed by recent data coming out of this relatively idyllic island county.

A sample of Picton, Ontario (population 4000) sewage sludge has revealed the 
extraordinarily high Aluminum level of 72,200 ppm.  In the surrounding 
territory, the Bay of Quinte Remedial Action Plan (RAP) has established the 
objective of 0.3 mg. per L/day Total Phosphorus, or an equivalent loading of 
1.8 kg./day--for all sewage plants in the B of Q area. It is my contention, 
borne out by the local sludge reading for Aluminum, that to achieve the RAP 
Total P goal--massive amounts of Alum is ending up in the sludge. And this 
sludge is being spread on Prince Edward County farm fields. Alum (aluminum 
potassium sulphate) is a chemical used for flocculation/phosphorus removal 
during the sewage treatment process.

To my knowledge, there has been no inquiry at the municipal level in the 
County into other chemical precipitation agents--designed to coagulate the 
suspended solids particles. As I understand, generally with other 
coagulants, e.g. iron salts (ferric chloride or sulphate) a common 
engineering opinion is that alternatives to Alum are believed not as 
effective and/or are much more costly. Could potential problems also be 
created with excess iron in the sludge? In my research, I've come across 
another successful coagulating agent--called Fenton's Reagent, which is a 
combination of ferrous iron + hydrogen peroxide--which produces an added 
disinfectant effect, and a lower production of residual sludge. The irony of 
the situation is that as the quality of effluent treatment improves, the 
volume and contamination of sludge increases.

There are various arguments presented in research studies, especially with 
pH changes in the soil--where both Al uptake into plants and the human 
health of those near spread sites with high soil levels have been at 
issue--along with a number of other (e.g. cadmium, mercury. lead, etc.) 
potentially toxic, so-called "trace metals."

In correspendence, via the Composting Council in the U.S--Will Brinton of 
Woods End Laboratory stated: "In addition to potential direct toxicity of Al 
as pH drops in soils, Al directly interferes with P uptake by plants, or may 
do so as its principal mode, and in this way exercises direct 
toxicity....Personally I am uncomfortable with the wisdom of adding much Al 
to farm soils in this fashion, as it may eventually become soluble as pH 
inevitably drops over time or with continued use of ammonium 
fertilizers....In an as yet unpublished report, we have conclusively shown 
in replicated field studies with high Al sludge and composted Al sludge, 
that plant toxicity may be exhibited at normal (~6.0) field soil pH values. 
Converting to a ferric sludge removed the apparent toxicity. Cross sectional 
analysis of plant stems employing Al staining showed cell-blocking, probably 
an Al-P precipitate. Does organic matter protect Al activity and make it 
relatively more toxic than a normal mineral soil would permit? We don't 
know. But caution with Aluminum is in order, and especially careful matching 
to soil geology is appropriate."

In an email from Ontario farmer Brian Holmes, he says "the typical range of 
aluminum in soils may be from 1% to 30% on a worldwide basis with naturally 
occurring concentrations varying greatly. Here we are considering Ontario 
soil, where the "mobility" of the aluminum is increased by low pH (acidic) 
levels--especially that of rain water. Therefore a typical problem with acid 
rain is the increased levels of aluminum that may then be found in soils. 
Aluminum in agricultural soils is not a required plant nutrient or trace 
mineral but is known to tie up phosphorus."

And even if we believe that all the research into the Al and Alzheimer's 
Disease connection may still be "inconclusive", there is enough evidence 
proving that high levels of aluminum in humans can accumulate in the liver, 
lungs, kidney, brain and skeleton and potentially result in damage to those 
body locations.

Finally, an article about the CSIRO "electrodewatering" technology 
(Australia), points out that it is well known in the wastewater industry 
that "alum-based sludges are very fine and extremely difficult to dewater." 
Conventional dewatering equipment typically produces very wet sludges; a 
liquid content of 75% is not uncommon. Therefore a lot of money is often 
spent on disposing of materials that are mainly water. In locations where 
transport or landfill costs are significant, there is considerable financial 
incentive to improve dewatering and hence reduce disposal cost."

In another analysis of the same sludge, Professor Rob Hale at the Institute 
of Marine Science (Virginia, U.S.A.) revealed the Picton sample contained a 
concentration of Penta-like PBDEs (in "brominated" fire retardants) that "is 
on the high to very high side of what we have seen elsewhere in 
sludge...even in the U.S. The Penta is the more problematic mix as it is 
accumulated efficiently and its compounds are the dominant ones detected in 
fish and people."
An article in The Walrus magazine("Everyday Poisons", Dec./Jan. 2005) noted 
that some Canadian politicians and health officials were finally starting to 
"heed the mounting evidence to support claims that the flame retardant 
chemicals swirling invisibly through our homes can cause neurological damage 
in children and impair hormone production in adults. According to some of 
the latest studies, even minute doses of brominated fire retardants impair 
attention, learning, memory, and behaviour in laboratory animals."

CBC-Radio's "Quirks & Quarks" produced a story that featured a panel of 
researchers studying the effects of PBDEs. Dr. Mehran Alaee is a research 
scientist with Environment Canada. He has measured PBDEs in the environment 
and, while he says the current levels are still fairly low, it's the fact 
that these chemicals are highly persistent and bioaccumulative that is the 
real cause for concern.
Dr. Linda Birnbaum is director of the Experimental Toxicology Division of 
the US Environmental Protection Agency. She says the study of PBDEs is 
perhaps most easily characterized by what we don't know, rather than what we 
know. Animal studies suggest a range of negative effects, in particular on 
developing organisms.
Sonya Lunder is an environmental analyst with the Environmental Working 
Group, an American research and lobby organization. She says animal studies 
are all we need to regulate these chemicals. She says if we wait for 
substantial human data we could cause tremendous damage to generations of 
children in the process.
Dr. John Jake Ryan is a research scientist with Health Canada, whose work, 
along with Dr. Alaee's, has helped shape a proposal that PBDEs be added to 
the list of toxic substances and banned from use in Canada. A final decision 
has not yet been made.

As a result of high levels of PBDEs found in breast milk studies in Sweden, 
the practice of spreading sewage sludge on farmland has been banned in that 
country--and several others in the EU. It is noteworthy that Dr. Hale found 
PBDE levels in North American sludge were on average 20 times higher than in 
Sweden, with 95% being the most carcinogenic Penta form of PBDE.
In 2004, the CBC featured a story on fire retardants in Canadian women's 
breast milk, that can be read at this link: 
http://www.cbc.ca/story/science/national/2004/06/07/pbdes040607.html

Here are some other useful LINKS on PBDEs:

http://ehp.niehs.nih.gov/members/2003/6559/6559.html#intro

www.checnet.org/healthehouse/pdf/fishtoxins_table.pdf

http://pubs.acs.org/subscribe/journals/esthag-w/2003/may/science/kb_pbde.html

www.mindfully.org/Pesticide/Sewage-Slduge-PBDEs.htm

www.ourstolenfuture.org/NewScience/oncompounds/PBDE/2001haleetal.htm

www.garynull.com/Documents/erf/HereWeGoAgainPBDE.htm

www.computertakeback.com/the_problem/bfr.cfm



In addition, Professor Chris Metcalfe of Trent University (Peterborough, 
Ontario) analyzed the Picton sludge for drugs and pharmaceuticals--and 
identified the presence of 12 drugs--including an anti-depressant (Prozac), 
caffeine, nicotine, beta blockers, anti-inflammatory/painkillers, cholestrol 
inhibitors, an anti-convulsant and anti-biotics. A visit to Dr. Metcalfe's 
website tells us his job involves: "determining the environmental fate and 
toxic effects of organic contaminants in the aquatic environment. In 
particular, is interested in the fate and toxic effects of halogenated 
aromatic hydrocarbons, polynuclear aromatic hydrocarbons, alkylphenol 
ethoxylate surfactants and prescription and non-prescription drugs in the 
aquatic environment. Also is conducting research on endocrine disruption in 
fish. Also have international research experience through work in Mexico, 
Argentina, Ecuador."

"Trentmagazine", a local publication, featured this description: "The Water 
Quality Research Centre is led by Prof. Chris Metcalfe, Trent's Dean of 
Research and Graduate Studies. He has been researching the concentration of 
pharmaceutical products, including antibiotics, blood pressure and 
antidepressant medications, and birth control compounds in the effluents and 
effluent outflows of sewage treatment plants. Although the Trent Water 
Quality Centre has produced the only North American data on drugs in sewage 
treatment plants and surface waters, there is much more research to be done 
in this area. Dr. Metcalfe and his team are currently developing methods to 
analyze several classes of antibiotics, musks (fragrance) compounds, X-ray 
contrast agents, antidepressants, and psychiatric drugs."

An article in Vitality magazine in June 2005 featured Dr. Metcalfe: "Chris 
Metcalfe is an environmental scientist at Trent University who studies the 
toxic effects of pharmaceuticals in the aquatic environment. In particular 
Metcalfe has studied what ethinylestradiol — the hormone in birth control 
pills — does to fish. Metcalfe’s research has shown that in concentrations 
as low as one or two parts per trillion, male fish become intersex, that is, 
develop female characteristics. “I think the story is pretty clear that even 
low concentrations of that pharmaceutical can have impacts,” Metcalfe told 
Vitality.

And that’s just one drug. There is very little research into other drugs and 
their effect on the aquatic environment, but the studies that are being done 
paint a somewhat scary picture. “There is a little bit of data coming out on 
some chemicals that are heart drugs, beta blockers,” Metcalfe said. “They 
indicate that at fairly low concentrations they can have effects on fish. 
But we are just starting to get those kinds of data.”

Metcalfe has three concerns about pharmaceuticals in the environment: The 
effect on aquatic organisms, the uncertainty regarding chronic exposure to 
compounds through drinking water, and the third concern relates to the use 
of antibiotics in large-scale agriculture operations and the potential to 
develop antibiotic resistant organisms in the environment."

More recent studies are providing evidence that some pharmaceuticals occur 
in high concentrations in sewage sludge and persist in soil for several 
months following the application of sludge to agricultural fields, and there 
is little information on their environmental fate or effects.

Following are some informative LINKS on the subject:

Drugs In Our Water (incl. C. Metcalfe)
http://www.cwn-rce.ca/index.php?fa=Media.showFeatureSept

"Excreted Antibiotics Can Poison Plants"
http://www.sciencenews.org/articles/20020629/bob7.asp

("Vitality")--Drugs In The Water (incl. C. Metcalfe)
http://www.vitalitymagazine.com/earthwatch_drugs_in_the_water

Pharmaceuticals In The Environment
www.envirotest.com/pdf/Pharmaceuticals%20in%20the%20Environment.pdf

Pollutants In Urban Wastewater and Sewage Sludge (UK)
http://www.environmental-expert.com/articles/article1031/article1031.htm

Environmental Side Effects of Medications
http://www.nature.com/embor/journal/v5/n12/full/7400307.html

Drugs Environment & Health
http://www.whp-apsf.ca/en/documents/fullCircle.html

Abstracts Pharmaceuticals Sewage
www.georgiastrait.org/Articles2006/PharmacueticalAbstractReview.pdf


The most potentially nightmarish realization is that none of these sludge 
components analyzed in Picton are regulated under Ontario's sludge spreading 
guidelines. Nor will they be included in the provincial Nutrient Management 
Act legislation. Nor do they appear to be on the immediate radar of 
scientists at the Ontario Ministries of Environment and/or Agriculture. This 
is just the urban sewage from one small town, so to project the provincial 
potential is staggering to the imagination.

The Precautionary Principle has been developed and recognized 
internationally as a guide toward preventing harm to ecosystems and humans, 
generally stating that: "When an activity raises threats of harm to the 
environment or human health, precautionary measures should be taken even if 
some cause and effect relationships are not fully established."  Several 
Canadian organizations, including the National Farmers Union, Sierra Club 
and the Canadian Infectious Diseases Society have recognized the potential 
health and environmental hazards of  sewage sludge and are calling for the 
use of precaution in the form of a moratorium on farm spreading--"where 
insuffucient data exists." Because of possible liability, insurance 
companies are refusing to insure farmers that spread. In southwestern 
Ontario, financially beleagured farmers from over a dozen Federations of 
Agriculture have launched a protest boycott on accepting sludge.

In the United States, a 2002 report by the National Academy of Science 
identified a "critical need..to reduce persistent uncertainty...about the 
potential for organisms and chemicals in sewage sludge to make humans ill." 
The Environmental Protection Agency's Office of Inspector General issued a 
March 2002 report reiterating a statement from 2000: "The EPA cannot assure 
the public that current land application practices are protective of human 
health and the environment." So American states typically have permitted the 
land application of sludge, based originally on the EPA saying the practice 
was safe. We now know that the EPA's basis for this opinion was a risk 
assessment that is invalid, because not enough research was conducted.

This is mirrored north of the border, at the Ontario Ministry of 
Environment. As public awareness increases and disinterest among farmers 
spreads, the MOE is becoming increasingly desperate to put a positive spin 
on the "beneficial use" of "biosolids" as a free "organic soil 
conditioner"--even attempting to do a superficial band-aid amendment of 
provincial spreading guidelines. But without a solid scientific basis for 
their sludge rules that has included up-to-date research on all the 
"emerging contaminants", the government of Ontario, like the American EPA, 
is quite frankly taking a huge gamble with the health of rural residents and 
their ecosystems. Equally disconcerting is the knowledge that the province's 
wastewater and sludge industry have far greater insider lobbying privileges 
than the citizenry is ever allowed--through a body called the "Biosolids 
Utilization Committee".

Nevertheless, bearing in mind the results of the Picton samples, is it not 
finally the time to conclude that what we know about spreading sewage sludge 
on farm fields makes it a bad idea--and what we don't know makes it a 
terrible one? To say that sewage and other blended sludges (e.g. pulp and 
paper mill wastes) are being spread under the provincial Guidelines does 
little to allay serious concerns whether these practices are safe or 
beneficial. In fact, there is increasing consensus from farmers, rural 
residents, scientists and independent researchers that this is a potentially 
disastrous experiment that is far from a "normal farm practice."

** Bruce Cattle is a freelance writer living in Picton, Ontario. He is an 
active member of The Safe Water Group (of Prince Edward County).