There is evidence that the natural heat phase of decomposition of hot composting kills potentially harmful toxins, bacteria, etc. But you'll have to look into that particular toxin. Some toxins break down naturally in sunlight and others require agents such as bacteria.

Make sure the horses were not "recently" wormed, and never rely on only one source of material for your compost.

Here is a link that might be useful: EnviroHorse

The daily wormers are fairly low toxicity, and should break-down with composting for 3-4 months. Not every horse owner feeds a daily wormer, some worm at intervals of 4-6 weeks instead; with those wormers, the manure might be better avoided for the couple of days after worming, if you could control when you collected the manure for your compost pile. BUT, if you have little to no control over when you can collect manure, and don't know when the horses were wormed, then composting the manure, mixed with a variety of other materials, for a period of no less than 3 months (better 6 months), should allow all the wormer toxins to break down. If you do a Google search for the half-life, or for the time frame for the break-down, of the chemicals involved (different wormers use different chemicals, although I THINK all the daily ones are the same chemical, whatever the brand name), then you should be able to find out more information. I used to remember the names and breakdowns of the various wormers, but my memory has turned to mush, and I would have to search myself to find out......

In any case, the wormers are toxic to worms and to the other microherd in the soil, not to people. The reason composting is recommended is so as not to decrease your microflauna population, not because it is dangerous to you. Many of the recommended wormers for horses are also used for people, i.e.; ivermectin is the usual medication for the treatment of "river worm", one of the leading causes of blindness in Africa.

To expand on my above posting, I don't mean to imply that wormers are totally non-toxic - for example, the one I mentioned for people, ivermectin, is very carefully measured according to body-weight, as are the doses for animals, be it horses, cattle or dogs, since too much CAN be harmful. BUT, the toxicity comes from eating or injecting too much of the wormers, not from handling/touching them. Once the wormers are "diluted" by passing through a horse, you won't have any problem with them - I doubt ANY of us plan to eat the manure as is! As long as the manure is composted, there should be no problem.

Thanks for the info. I'll try to figure out what the potential medications are and will do a search to find out how long it might linger - and what it might break down into. I suppose it would be a similar issue with cow manure or other animal wastes.

Thanks

Tanya

A daily wormer would be something used for a short time, not something used over a long term. If someone does there is a bigger problem than the worms the horse has. So, for the short time that wormer is used you might want to consider not using that manure, and if that person gives that wormer over a long period of time to not use that manure at all. However, the medication in the manure, if the manure is composted as it should be, will not have much affect on the soil.

Kimmsr, I know a number of people who feed a daily wormer for the life of the horse - I don't agree with them, but... Either they can't or don't want to figure out when the next worming should be done, or their horse is in a situation where it is constantly exposed to being infected with worms - a heavy showing schedule, being boarded in a barn where many horses move in and out, etc., etc. - and they want the peace of mind of knowing that their horse is protected.

The latest thinking on worms/worming is to treat mature horses in the spring and fall with one of the broad-spectrum wormers, and then treat again only after doing a fecal egg count, and do another FEC a few weeks after dosing the horse to double-check - it turns out that the rigid schedules aren't as effective as thought, and some horses are more and some less susceptible to infestations than had been thought. And some wormers kill some worms or life-stages and not others, so.... Foals and broodmares should be treated on a different schedule, due to their specific needs. There is the fear of various parasites developing a resistance to the wormers, as happened with the commonly used wormers used 20-25 years ago, so using the effective wormers less often and more effectively is seen as a very good idea.

I've been hot actively composting and selling my homemade compost to customers and local farmers for over 8 years now. About 75% of my compost is raw and aged horse manure mixed with untreated sawdust and hay, from a large local equine clinic. The other 25% is leaves, grass clippings, coffee grounds, and fish scrap wastes from a local seafood shop.

I also highly moisturize my large hot piles with dry molasses tea recipes in order to speed up the aerobic microbial growth and decomposition of all the proteins, carbohydrates, mild toxins, pathogens, and any other potentially "bad stuff" in my rotting organic matter. Since all beneficial soil microbes love sugars, the dry molasses applications greatly reduces my hot composting decomposition times to about 1/2 the normal decomposition times to develop mature healthy compost.

I've never experienced any issues with my mature compost product being polluted with harmful chemicals or toxins. As a matter of fact, since I'm a totally 100% no-till sustainable farmer, all of my garen beds and lawn is totally loaded with lots and lots of healthy earthworms, and other healthy beneficial soil organisms. I can easily see that without using a microscope or any biological soil test.

All organic and sustainable farmers know that earthworms are highly sensitive to harmful chemicals and toxins and soluble fertilzers and pesticides in topsoils. The fact that I have approx. 7-10 earthworms every square foot of my garden beds during the warm months, proves to me, that nature is doing it's job by balancing and neutralizing these "greens" and "browns" properly via the amazing aerobic soil microherd.

Keep in mind that composting methods is about balance and moderation. And most of all just have fun!

Happy Gardening!

dibbit said, "The latest thinking on worms/worming is to treat mature horses in the spring and fall" but that was the latest thinking in the 1960's, so what has changed? Anyone that gives their horse a pill daily to eliminate worms either is using the wrong stuff or is too cheap to have a proper analysis done. No one should be doing that because it is totally unnecessary, ecologically unsound, and unnecessarily expensive.

I remember in the 80's giving the poor horse that nasty worming paste in spring and fall. Then after keeping my horse in a stall overnight we would eagerly check the manure the next day for the 'body of evidence'. Being only teens at the time we were more fascinated than grossed out. AHHHH the good old days!

There are daily worming products that some horse people use (forever). I worm my horses every 90 days, then I keep that manure (for several days) separate from my garden composting manure. I don't know if it is harmful or not, but I prefer not to find out.