Tagged: Lindsay Brown
Biosolids panic – rebuttal
Responding to my response to his earlier response to Lindsay Brown’s letter to HRM Councilor Jerry Blumenthal decrying council’s decision to spend $50,000 repeating decades of studies that have confirmed the safety of biosolid use in agriculture, Cliff White writes:
Halifax Harbour is certainly cleaner then it was. Well, as long as it hasn’t rained in three days, and thank god we get so little precipitation here abouts. And it would be churlish of me to mention that the sewage plants don’t meet the new federal regulations for what can be released into the ocean, so I won’t.
Let me just point out that I originally sent the list from USEPA because you had suggested there was no scientific basis for the concern people were expressing about exposure to sewage sludge. My point was, and is, that there is valid scientific concern, or governments and other institutions, across the developed world at least, wouldn’t be testing the damn stuff.
Since 1999 Centre for Disease Control in the US has been measuring 219 chemicals found in people’s blood and urine. These of account for only a small number of the many tens of thousands of chemicals in use today, many more of which likely end up in our bodies. Besides the chemicals in the sludge, of course, there are also pathogens and there are many peer-reviewed papers looking at how sludge containing these products effects the environment, people, and other animals who live in it. The reality is the debate goes on, and it’s a valid one. It isn’t just the individual products in our bodies, the chemicals, heavy metals and bacteria, but how interact with one another.
If people are happy adding a few more dozen chemicals to their internal environment, that’s fine with me. But those who prefer to limit their intake should have an equal right to do so. If farmers want to use sewage sludge on their land, then the resulting products should be labelled to indicate they were produced in this way. Those who wish to add a few more of the above mentioned chemicals and such to their internal environment can do so freely, and everybody else can continue to try and avoid them.
Now there’s a thought. Does this mean the thousands of Nova Scotians who pay extra for local, organic food grown in untreated farm manure should have the benefit of warning labels to alert them to the pathogens and heavy metals that time-honored organic fertilizer contains? Here’s a slide Andrew Carpenter of Northern Tilth presented to the 2006 New England Residuals and Biosolids Conference:
So, poultry manure spread on fields has 48 times as much fecal coliform bacteria as uncomposted municipal biosolids; and 65,000 times as much as composted biosolids like those produced at HRM’s new plant. Cow manure has 125 times as much fecal coliform as untreated biosolids, and 171,000 times as much as composted biosolids.
For trace amounts of heavy metals, the picture is more mixed:
The values shown are in parts per million. NT means not tested. Biosolids and poultry manure were about on a par for most metals; cow manure slightly lower. All three were well below the levels contained in phosphate fertilizer. Remember, we are talking about metals that can be harmful in high concentrations, but which are essential to life in very small quantities. That’s why they are found in vitamin supplements:
The level of heavy metals in Rite Aid Central-Vite Multivitamin-Mineral tablets dwarfs that in biosolids and untreated manure. Of course, Rite Aid is a US brand, but Canadians can get multivitamin mineral tablets at — what do you call those places? Oh yeah, health food stores.
Further reading:
- FERTILIZERS, MANURE, OR BIOSOLIDS? – Researchers compare the benefits and risks of fertilizers and soil amendments by Steve Spicer in Water Environment & Technology Publication, Vol. 14, No. 7, July 2002, p. 32
- Biosolids verses other Plant Nutrient Sources: A Cursory Comparison of Benefits and Risks, presented by Andrew Carpenter of Northern Tilth at the New Engliand Residuals and Biosolids Conference, 2002.
- Biosolids: Targeted National Sewage Sludge Survey Report – Overview, US Environmental Protection Agency, 2009.
A Halifax resident writes her councilor – more feedback
Former health inspector Bill Bailey writes:
Kudos to Lindsay. Unfortunately, because politicians’ skin is made from elephant hide, they will probably take it as a compliment.
And a Halifax reader notes that this week’s Rona flyer features “eco friendly” Milorganite, at $7.79 for a 16.3 kg bag, “for better results NATURALLY.”
As noted previously, Milorganite is the great-granddaddy of recycled, composted municipal sludge. So it’s OK to spread Milwaukee’s venerable composted sludge on Halifax vegetable gardens, but heaven forfend we use Halifax’s modern stuff on municipal flower beds.
And one more. Colin May writes:
Reminds me of the arguments against incineration 20 years ago: “Heavy metals, blah, blah, blah….risk analysis sucks, blah, blah, blah…. I belive it is bad…”
- Science is Good when they discuss global warming.
- Science is Bad when it comes to sewage treatment and incineration.
- Science is Bad when discussing fluoride in our water.
Just face up to the fact that 10-15 percent of the populace will oppose almost any proposal. Politicians should just ignore them because to do otherwise will only encourage the perpetual worriers whenever something new comes along.
In my opinion breathing is dangerous for your health. It is the last thing a person does before dying and therefore we should all stop breathing. Statistics prove my assertion.
A Halifax resident writes her councilor – feedback
Contrarian friend Cliff White doesn’t share Lindsay Brown’s impatience with HRM Council’s decision to spend $50,000 studying the safety of fertilizer derived from the municipality’s sewage treatment plants.
Among other things, she mentions studies that go back eighty years. I’d suggest that studies going back even half that time wouldn’t be testing even half the chemicals, toxins, and metal compounds likely to be found in today’s sewage. Since any cursory search of the literature will show that not all of these products are removed at the treatment plant, three questions arise:
- First, how effective are our local sewage plants are in extracting heavy metals, toxins and other chemicals before it becomes sludge and then fertilizer?
- Second, what are the national and provincial standards for levels of these products in fertilizers?
- Finally, are these standards adequate to protect both the environment and human health?
A quick search of the literature will show that different countries have widely different standards in this regard, suggesting that this is a legitimate area for concern. Given the reasonable scientific concern regarding sewage sludge I don’t think a study of the local stuff is unwarranted.
In an earlier letter, Cliff forwarded information he extracted from a 2009 US EPA Report.
The sampling effort collected sewage sludge from 74 randomly selected publicly owned treatment works in 35 states. Samples were collected in 2006 and 2007. The TNSSS Technical Report provides results for 145 analytes, including:
- four anions (nitrite/nitrate, fluoride, water-extractable phosphorus),
- 28 metals,
- four polycyclic aromatic hydrocarbons,
- two semi-volatiles,
- 11 flame retardants,
- 72 pharmaceuticals, and
- 25 steroids and hormones.
Some analytes were found in all 84 samples, while others were found in none or only a few of the sewage sludge samples.
After the jump, more extracts from the report, detailing the number of samples in which various chemicals were found. That list will probably scare some readers. Certain environmentalists like to cite such lists precisely because they sound scary, and because they lend a false aura of scientific credibility to their arguments. Such lists are all but meaningless without two essential pieces of information:
- In what concentrations were the chemicals found? (For many chemicals, minuscule amounts are both routine and harmless.)
- What level of exposure to people, plants, or animals would result if the sludge were used for its intended purpose? (How much actually gets to people is the real worry, and Cliff’s list tells you nothing about that.)
To answer these questions, scientific risk assessors use a model known as source, pathway, receptor. In the case of a person who eats carrots grown in soil treated with fertilizer derived from composted sewage sludge, the sludge is the source, eating a carrot is the pathway, and the person is the receptor.
For each chemical, the risk assessor will determine the amount present in the sludge, and the amount that might make its way into a carrot and then into a person who eats the carrot. The risk depends on the actual exposure a person might experience. These calculations typically use ultra-conservative assumptions: the receptor is a developing child; the child eats only vegetables grown in soil treated with the fertilizer; Large amounts of fertilizer are used.
This is exactly the kind of analysis used to set allowable levels of Cliff’s scary sounding chemicals. Find the Canadian Council of Ministers of Environment (CCME) report on this process here [pdf]. Regular sampling confirms that composted Halifax sewage sludge meets these standards. Dozens of municipalities have safely used sewage sludge for decades, with less advanced equipment that that used in HRM. And let us not forget, Halifax’s sewage treatment plants solved a real environmental menace–the dumping of raw sewage into Halifax Harbour.
For all these reasons, real environmentalists should be delighted, and HRM Council should not waste public money pandering to anti-science zealots who will never be persuaded on this issue. Read more »
Steve Streatch and the Lobby of the Lazy
Contrarian is not the Nova Scotia blog of record, but I don’t want HRM Council’s latest act of craven irresponsibility to pass uncommented upon. Neither does Contrarian reader Lindsay Brown, who writes:
What is it about the Halifax lifestyle that produces more embarrassing stuff in just two weeks than you can put in a single opaque garbage bag? What am I missing?
The facts are simple. Nova Scotia was a pioneer in trash sorting, diversion, and recycling, thanks to visionary provincial legislation. These measures were necessary to slow the pace of landfill growth, given the horrendous obstacles to siting new dumps. After rapid early progress, HRM stalled at about 60 percent diversion. That means roughly four out of 10 items that could be diverted, composted, or recycled instead require expensive secondary sorting or end up in landfills.
The reason is no secret: Many people can’t be bothered to sort or recycle. That lobby of the lazy, led by Councillor Steve Streatch, famous for fretting that immigrants will dilute Nova Scotia’s population, persuaded a majority of HRM councillors to reject staff proposals to join many other Nova Scotia municipalities in mandating clear plastic bags for most trash (with a single opaque bag permitted for unmentionables and unviewables). Moistened finger to the wind, Mayor Peter Kelly followed the noisy band.
Someday, a future mayor and council will have no choice but to do the right thing and pass the rule it rejected this week. The financial, environmental, and most of all, political cost of siting new landfills will force their hand. In the meantime, we will waste more money and cause more damage to the environment. Thanks, boys.
More begrudgery
Contrarian has some highbrow friends, including Mike Targett, who weighs into the begrudgery debate quoting Wittgenstein: “The meaning of a word is its use in the language.”
That is the classic formulation of descriptivism, the reigning philosophy among lexicographers. The trouble with descriptivism is that it leads to definitions like this one, from Merriam-Webster: “biweekly: 1. occurring twice a week; 2. occurring every two weeks.” It’s true, people use biweekly to mean both things, but sometimes you need a prescriptive dictionary to tell you what a word really means. I’m with Lindsay Brown on that score.
