Biosolids, Antibiotics, Estrogen

The GMO discussion has been fascinating--and I want it to continue--but here's another topic that might be worth discussing; one on which it'd be nice to get some informed opinions. Last night, I was part of a discussion that focused on the use of biosolids (sewer sludge) used in compost. The city I live near, Sierra Vista, AZ has had a big-time municipal compost program for a number of years. Recently, they began incorporating biosolids into the compost. Some folks are worried about residual antibiotics and hormones (mainly estrogen, I think) in the finished product. To be upfront, my initial, fairly uninformed opinion, is that the concern over such items in compost is, to be blunt, ridiculous. Assuming that such things are present in a "potent" form after surviving the sewer and compost process, I doubt that they could enter a plant from the soil anyway. Anyone have facts, opinions, or comments? Let's get this ball rolling!

Willy, we don't use biosolids and haven't for many years because there are viruses, such as the AIDs organism, that just aren't affected by the usual treatment methods. I know that back when we were looking at the issue it was always strongly advised to use them only on ornamentals and never on food crops. But that was a very long time ago.

HIV essentially cannot survive outside the body. That's why AIDS is not a threat via casual contact. It requires the old "exchange of bodily fluids" to be transmitted.

you are being specific, she is not. But on this note, there ARE several viruses whose life expectancies are not short, that live on even in the soil you percieve as safe. Some are viable, cannot be filtered out, yet, plants appear to be a filtering system for many things in the earth, some fruits retain traces of these, many people also retain traces of these things throughout their life. So do other animals. In order to be worried about these you would need to find the one specific thing you wanted and find out in controlled conditions what your chances were of this item coming back to bite you. And keep an open mind, do not assume because someone else tells you it won't, that they have the only truth.

Willy, you're right about AIDS; I don't know what I was thinking. But there are definitely other disease organisms as well as heavy metals, pharmaceuticals, and volatile organic compounds that aren't dissipated by the usual methods.

You're right, some viruses can certainly persist for long periods of time. They're also on every surface we touch. I just had a funny thought--re-useable shopping bags could be considered a source of viruses, since we place them in shopping carts, a "well documented" source of contact with bacteria and viruses. I think perhaps we worry too much about really tiny risks. One of the real ironies of the discussion on biosolids that I was involved in the other night was that two of the three anti-biosolid folks were quite obese, a definite health risk that, as mentioned in the GMO discussion, many of us ignore.

One interesting thing about biosolids that I didn't know is that they aren't "poo". Instead they are the bacteria that ate all the "poo".

Willy,

Actually biosolids are used on commercial farming and are considered "organic".
http://www.sourcewatch.org/index.php?title=Hou-Actinite

Virtually cities in every state have biosolid programs.

I too would be concerned about all of the medications and other ingredients people put down their toilets. I am sure much of it is microbially degraded but I would be hesistant to use the stuff on my plants.

I know a farmer here in PA that uses biosolids and he gets a bunch of tomato plants coming up out in his corn because evidently the human body does not digest the seeds and the composting process used here doesnt destroy all the seeds.

Using liquid manuers and biosolids has cause many a people to get sick....especially with organic foods.

Give me some good chemical fertilizer instead please!

I believe that the use of biosolids is forbidden if one wants to be certified organic.

http://water.epa.gov/polwaste/wastewater/treatment/biosolids/

Looks like the EPA has looked into the eefects of some of the pollutants found in biosolids and their affects to the environment and the crops that might be grown and have said they are relatively safe.

True...biolosolids are not approved for organic use...http://www.ecfr.gov/cgi-bin/text-idx?SID=677fd6074135ef561960b29b8b731059&node=7:3.1.1.9.32.3.354.4&rgn=div8

Animal biosolids and manuers are however approved...and this has sickened many people who have eaten organic crops.

Just to be clear, our city is incorporating biosolids into compost (mainly chipped wood). Use of biosolids has allowed them to eliminate spraying the compost rows with water (important in the arid southwest), eliminated the need to purchase nitrogen to "heat" the rows, and eliminated the need to truck the biosolids to a landfill. And the compost is ready to use in less time than before. The biosolids are not being sold separately.

This message was edited Feb 10, 2014 4:23 PM

This was in the wrong thread - sorry!

This message was edited Feb 11, 2014 8:05 PM

I have had increasing health problems due to chemicals in the house and garden, and have read too many stories about pharmaceuticals found in our waterways. I buy as much organic food as possible (in addition to what I grow) from local vendors that I know do not use biosolids. I won't use them as a matter of principle regardless of published data. We all know data can be bent in favor of the claims.

I'm overweight by maybe 10 pounds, but not obese by any stretch. If I were more active at my age (73) I'd probably shed those pounds.

This message was edited Feb 10, 2014 2:39 PM

Darius--the obesity comment was related to a discussion is the GMO thread where it was noted that some people focus on unknown or poorly understood risks yet ignore known risks like obesity. For the record, I carry a few extra pounds myself. it's my way of storing food in the event of a calamity. :-) or so I tell myself.

Two questions about biosolids:

1) Where do the heavy metals in biosolids come from?
2) What is the concern with antibiotic residues in soil?

Willy, my remark was just a casual note that I don't think there's any evidence linking obesity and choosing carefully what is best to eat for good health. I hate seeing grocery carts laden with chips, sodas and other junk food pushed by heavily overweight adults AND children.

I water my garden from water in a spring that comes down/through the mountain, NOT city water, so I'm less concerned about antibiotic residues or heavy metals in my soil. I do think heavy metals are more likely than antibiotic residues simply because many are airborne as a gas and fall to earth naturally.

Not all heavy metals are toxic to humans. In small quantities, metals such as iron, copper, manganese, and zinc are essential for good health. Arsenic is the most common cause of acute heavy metal poisoning in adults (but the source is not from soils). Arsenic is released into the environment by the smelting process of copper, zinc, and lead and from manufacture of chemicals and glass. Lead on the other hand is the leading cause of heavy metals poisoning with major source coming from soils.

It is important to note that plants do not absorb or accumulate substantial amounts of lead. Lead does not readily accumulate in the fruiting part of vegetables and fruit crops (e.g. corn, beans, squash, tomatoes, strawberries, and apples). Since lead is tightly bound to clay particles, higher concentrations of lead will therefore be on surfaces of leafy vegetables from lead laden dust (e.g. brassicas), and on surfaces of root crops (e.g. carrots and potatoes) if soils are contaminated. Actually, there is more concern about lead contamination from external lead on unwashed produce than from actual uptake by plants. This raises the need for everyone to always wash their produce before eating/cooking and places a big responsibility on growers to always wash their leafy vegetables before marketing them since lead laden dust can blow from distant places. Remember that soil contaminated with lead looks and smells like normal soil. Lead does not biodegrade since it has a half-life of about 53,000 years.

http://smallfarms.oregonstate.edu/sfn/su10toxicmetals

I read (in just one or two places) that a major source of lead contamination on crops was from leaded gasoline. The exhaust went into the atmosphere and the lead came down on dust or with rain and dew. It would settle on leaves and then be eaten.

My guess is that heavy metals in biosolids arise mainly from the fact that huge volumes of water come in and then settle. And I guess some people flush zinc batteries, copper pennies and nickles down the toilet. I've heard that some storm drains used to pour into sewage treatment plants, and those would have caught atmospheric lead from leaded gasoline.

Unless the heavy metals were truly in solution, they would stay with the solids and become more concentrated as water was removed. Then even more concentrated as the solids were digested further by being digested by microbes and then those microbes eaten by other microbes, with some of the matter being removed as CO2, H2O and methane at each stage


Since 1993, the EPA (Code of Federal Regulations Title 40, Part 503 = 40 CFR, Part 503)
mandates testing for at least these 9 heavy metals :
- arsenic,
- cadmium,
- copper,
- lead,
- mercury,
- molybdenum,
- nickel,
- selenium and
- zinc.
It also sets several kinds of regulatory limits for what may be done with biosolids that exceed those limits:
- CCL = Ceiling Concentration Limit
- PCL = Pollutant Concentration Limit
- CPLR = Cumulative Pollutant Loading Rate Limits for Biosolids
- APLR = Annual Pollutant Loading Rate Limits for Biosolids

http://www.caes.uga.edu/applications/publications/files/pdf/B%201353_2.PDF

There's a DG member who is a senior engineer or "schiesmeister" (his term) at a treatment plant, and he says those testing procedures are performed and enforced very seriously.

My guess is that, before 1993, heavy metals were not tracked or controlled at some plants. Some gardeners learned of that, and gardeners have been objecting to "heavy metals in biosolids" ever since.

Heck, not many decades ago, sewage treatment plants were just then being demanded and built to ~reduce the amount~ of raw sewage being dumped into rivers!

P.S. One thing to remember: all these metals ARE found in natural soil and always have been. Some soils have lots more than others, due to the rocks the soil developed from as well as historical sources of pollution. Very possibly plants grown in modern 100% Class A biosolids would have fewer heavy metals in their root zone than plants grown in pure natural soil in some parts of the country.

Speaking of heavy metals, many kinds of granite release radon. 100% natural, 'organic' radon.

Not a small amount either: in some parts of the country radon in the basement can have as much medical effect as 1-2 cigarettes per day. I was a little miffed when I lived in a basement for 2 years, THEN tried to sell the house and was told we lived in a "radon area" and would have to have the basement 9and well) tested before we could sell it. We passed but it was a squeaker, and homeowners were allowed more than one test to get a passing grade.

Speaking of which, we found a second well on the property after moving in. I assume that it failed a test, and the builder drilled another hole to see if it would come in any cleaner. New Jersey; what can I say?

I guess the realtor handled that "for us" when we were moving in and hid it in the fine print.

Life is risk.

Darius--two comments. Number one, lead does not have a half-life--lead is "forever" (there are some isotopes that do decay, but they are trivial in the big picture). Second, regarding obesity again: one of the vehement anti-biosolids people in the discussion I was involved in has a calf as big as my upper thigh, maybe bigger. She is grossly, grossly obese. Nonetheless, she evidently chooses to ignore an obvious health threat--obesity--and focus instead on whatever uncertain dangers lie in the use of biosolids on a field of dirt. A second anti-biosolids person wasn't too far behind in the obesity department.

No hostility intended here, just trying to make some points clear.

So, is this just too crappy of a subject to continue with it? :«)

WIlly,

I arrived late, but I would have to argue in favor of the use of bio-solids with human wastes. From what I can tell, the risk of infection is not that great. Many farmers in developing countries basically use raw sewage as their only available irrigation. There are higher levels of waste-related disease... but is that caused by the irrigation, or washing and bathing with contaminated water from the local river? After all, the Chinese have survived successfully for over 4000 years while using "night soil" to fertilize.

It does seem that lead and heavy metals might be more of an issue. Our industrial societies throw away (and flush) materials that the historical Chinese farmer never saw. The risk may be more from those issues than the possible germs. I can't see hormones or pharmaceuticals being much of a risk from sludge, either. The levels of dilution that is obtained when flushed and processed is infinitesimal. I take a weekly hormone shot of 1.5 ml of the hormone. I can't even imagine how many gallons of processed sewage it would take to produce that level of hormone.

To be completely safe from contamination from possible bacterial disease, use the sludge on crops that require cooking and avoid crops that are consumed fresh (and possibly unwashed).

>> It does seem that lead and heavy metals might be more of an issue.

For some reason, I do trust sewage engineers to do the required heavy metal tests and report them honestly. I hope this is one kind of governmental regulation that we can all agree is a good thing.

I used the think that "lots of farms" used biosolids, but then I read something that said only some very small % of ag land used biosolids. maybe 1% or less. Still, some of what we eat from supermarkets was intentionally fertilized with tested biosolids.

Some stuff from supermarkets was unintentionally fertilized when harvest workers pooped in the fields and kept picking. Bon appetite!

Hopefully more biosolids go to orchards than lettuce farms, since even Class B biosolids are approved for farm use, if rules are followed about time between application and harvest!

I am determined to keep this thread going. :«)

Earlier, I had asked where the heavy metals in biosolids came from. It was a somewhat rhetorical question, as I am pretty sure that virtually all of them come from the water in the sewage system, with a small amount coming from the feces and urine that were excreted by us humans. I could be wrong, but I don't believe many sewage systems incorporate storm water. Please correct me if I am mistaken.

Anyway, the real bottom line is that ALL water "on the earth" contains heavy metals and every other darn thing that is soluble in water, aka the "universal solvent". Humans have been drinking this water forever. I don't mean to imply that we should willy-nilly be consuming heavy metals. We have learned that they can be dangerous "in excess" and we now control many uses of heavy metals. Chrome bumpers are gone--cadmium plating is largely being phased out. Our water is tested for heavy metals. I know our compost facility is required to check for at least some heavy metal residues.

As for hormones, I don't know the concentrations or the effects, but, unless y'all want to quit creating feces and urine, these things need to go somewhere. My suspicion is that these residues are extremely minor in amount and that, if "spread upon the land" after sewage treatment and composting, the few remaining molecules themselves are large and infrequent enough that they pose no threat to us by being absorbed into plants. Same thing for viruses and bacteria. Good grief, these organisms (are viruses organisms?) are on every surface we touch. They are on every bite of food we eat and in every breath of air we take in.

We seem to be so conscious of the little, teeny risks in our life--and thanks to science we can now detect these risks down to parts per billion and even smaller--but, if we want to continue to enjoy the lives we live, it seems to me we need to learn to accept some tiny risks in exchange for doing the greater good. In the case of biosolids--organic material by the way--this means reusing them for their nutritive value instead of putting them in a land fill. When was the last time you read good things about land fills?

OK, so maybe some informed, knowledgeable reader can show me why I'm dead wrong. I'm OK with that; I've been wrong before. In the meantime, I think terms like "heavy metals" and such are just convenient shorthand that allow us to reject pretty much anything we want to reject.

I hope someone can provide some "real facts" on this issue. I am definitely not that person, though I obviously have strong opinions. lol So, my question this: do biosolids represent a measureable threat to human health?

Willy, I think you hit it on the nose.

Organic farmers seem to think there are risks. If you have biosolids with heavy metals or any harmful bacteria like E. Coli and they splash up onto your spinach from the soil then you got a problem. Especially if they are not washed off well.

I think it a depends how much biosolids are used and how well they are composted both prior and after they come in contact with the crop.

Willy said:

>> Anyway, the real bottom line is that ALL water "on the earth" contains heavy metals ...
>> ... Humans have been drinking this water forever. ...
>> ... We have learned that they can be dangerous "in excess"
...
>> Same thing for viruses and bacteria. Good grief, these organisms (are viruses organisms?) are on every surface we touch. They are on every bite of food we eat and in every breath of air we take in.

I agree, at least 90% agree.

The only way I would differ at all is the old cliché "the dose makes the poison". Footnote *1

If treatment plants DID concentrate heavy metals, for example by evaporating most of the water they remove from sewage, then they might have increased the levels in the solids far above their starting points.

Like a potted plant that never gets flushed, but only fertilized and watered lightly, ALL the soluble minerals and salts that enter the pot stay there until you have saline crusts forming.

Heavy metals, bacteria and viruses are as you say, everywhere. But the heavy metals probably become concentrated as water is removed from biosolids. I can't swear to that: the sewage engineers might decant them along with clear treated water and return the metals at low concentrations to rivers or oceans. Or maybe they use ion-exchange resins to remove them into 55 gallon drums ... all I know is that now, they have to test every effluent and pass the tests for each pollutant in each stream they release.

>> In the meantime, I think terms like "heavy metals" and such are just convenient shorthand that allow us to reject pretty much anything we want to reject.

I've read the cliché that "biosolids have heavy metals" in so many places that I could believe that many treatment plants used to leave higher level of some metals in the biosolids that they do now. If ti was true at one time, gardeners will probably be repeating it and quoting each other for 100 years.

The bacteria would also be concentrated during sewage treatment, except that different kinds of bacteria (and the viruses that prey on them) eat each other as the biosolids are digested. The idea is to reduce the number of human pathogens to "indetectable" in Class A biosolids, and below stated limits for the Class B biosolids. I'm sure they specify the tests that define 'indetectable", since some PhD candidate could always find a way to detect ANYthing if his thesis depended on it.

>> if we want to continue to enjoy the lives we live, it seems to me we need to learn to accept some tiny risks in exchange for doing the greater good.

I agree completely! I have read in many places that most people seem to have illogical reactions to risk estimates. Few of us worry much about very hazardous activities like crossing a street without looking or driving a car after drinking, but lots of people panic at the thought of flying (so much safer!) They'll smoke tobacco and eat tons of fat and grease (proven high-risk killers) but worry at length about sugar crystalized from GM sugar beets. (It's the sugar that will kill us, if anything, not the genes in the plant from which chemically pure sugar was crystalized.)

>> I hope someone can provide some "real facts" on this issue.

Sorry, I only have firm opinions, and those depend on trusting the engineers running treatment plants and the regulators checking their test reports.

I have gone hunting online, and only found that biosolids ARE used on agricultural lands and in making compost for garden and farm use. So they aren't wasted, and the people making them, buy them and using them seem to think it is safe enough.


Footnote *1

RE: "the dose makes the poison"

All things are poison, and nothing is without poison;
only the dose permits something not to be poisonous.

Paracelsus, 1525 + or - 15 years

Or, in a pharmacology class I took once, they used the term "drug" a lot. They finally defined it as anything, chemical or physical ingested by, breathed by, or applied to any subject of interest. For that purpose it covered air, water, solids, other liquids or gases, radiation, light, sound, smells and anything else that might interact with any of the above. I didn't think to ask whether it would have applied to sleep deprivation or rap music, but I'm sure that, if either affected drug absorption, metabolism or interactions, they would have lumped it in.

Paracelsus said that everything is a poison, and my prof would have said that everything is a drug. Then he would have added that not every drug has a therapeutic purpose, and sometimes they have very toxic side effects.

(I think the reason that they lumped toxins in with drugs is that, in pharmacology, everything interacts with everything else, and they didn't want to keep qualifying phrases like "drug interactions". )

One way in which they advanced beyond Paracelsus in 500 years is that now they know it's not only DOSE that matters, but also "scheduling". It might make a big difference whether you take something in the morning or at night, on an empty stomach or with meals, with milk or with orange juice, or just a tiny amount every two hours.

Water is toxic in the right amount....

This message was edited Feb 25, 2014 5:12 PM

I am sure that some concentration does result from evaporation and such, but biosolids are, as you point out, tested for these and "fecal coliform bacteria" (in my town). No testing for viruses, nor antibiotics. According to the compost manager, no such tests are required and, I don't know, maybe don't exist in a practical form. I am skeptical that biosolids spread over the land are a risk to us via ingestion of plants from in that land.

Also, I think at least some municipalities do "waste" biosolids. We apparently took them to a landfill until starting to incorporate them into compost recently. Las Cruces, NM does have a biosolids program and, of course, Milorganite is biosolids from Milwaukee. I'm sure there are many more.

>> I am skeptical that biosolids spread over the land are a risk to us via ingestion of plants from in that land.

Me, too. With the possible exception of Class B biosolids being applied to leafy crops too close to harvest (illegally) and then the crops not being washed on the farm or distributor or at the consumer's sink.

>> Also, I think at least some municipalities do "waste" biosolids.

Wow, "never underestimate the power of human stupidity"!

Or maybe, if there are no local composting companies or enough farmers with trucks close enough that the gasoline isn't too expensive, giving them away is not an option.