I have started preparing a small piece of land for growing vegetables. To my disappointment, I quickly realised that it has been used in the past years as a dump site. Among other bigger pieces of rubbish there are several tiny pieces of plastic and nylon. It’s hard to estimate their quantity but I’d say there is one every 10 cubic cm. I am removing all the garbage and the smaller nylon pieces I can see, but I am wondering if it would be safe to grow vegetables there, or if the plastic has already polluted the soil and I should move to another place.
Plastics is not a real problem, but construction trash is not a good base for vegetable gardens: they could contain a lot of heavy metals (e.g. from paints and coating). Additionally the soil is usually not stable: chemically (different pH and ions in different parts), and structurally (you will be surprised on how much empty space there are, roots doesn't like air).
The safest way: do a raised bed, putting a plastic sheet below. In this manner you split the bad soil with controlled soil. If the construction trash is not too large and/or too depth, you can move them away from the zone you will do the garden, and there you put new soil. This should "filter out" most of dangers, and very small quantities of heavy metals are not so bad (and often found in rocky soils). This should be done with construction machines, not manually.
Pieces of plastic, nylons, if it wasn't a public dump site I doubt there will be major problems. no big deal. I would make raised beds to encourage drainage for your plant's roots.
In your case, I would most certainly get a soil test done by your Cooperative Extension Service. Tell them what you are worried about and if they don't do tests for major pollutants I would go spend the money to have a private outfit test your soil.
It would be well worth the money. Plastic has been studied and seems to be detrimental only as a bottle or cup or baby bottle, holding liquids and/or being heated which allows the BPA into the food, water within bottles and canned goods. Otherwise, THE FDA says it is minuscule amount. ha ha ha.
I don't trust anything any government or official body says. Fluoride in your drinking water is far far far worse. The fact they allowed fluoride to be dumped in our drinking water when there were absolutely no tests saying it was beneficial for teeth or health in anyway...for 80 years, now? Industries get fined big time dumping it in the ocean, near aquifers and fresh water, why would they get paid to dump it in our drinking water?
Get soil tests done. Will you be watering with tap water or hopefully well water? Fluoride is taken up by plants readily as are heavy metals. When we eat our vegetables we eat any heavy metals or fluoride that has been stored in our plants. When we water with city water our plants get lots of heavy metals, lead, arsenic and definitely fluoride from the water we are supposed to be able to drink safely.
Chemtrails have been finally taken out from under the 'conspiracy' label. They spray chemicals to act as a nucleus for water droplets and those chemicals are primarily heavy metals. Look up the patents on Geo Engineering...they go back to the 20's 1920's...and are still very much in force today and covering our skies. Fluoride would be another important matter to research. There are excellent videos.
This chemical spraying IS raising the heavy metal content and raising the pH of all our soils and fresh water sources. If you are using tap water with chlorine and fluoride (hydrofluorosilicic acid), lead and arsenic usually come with 'fluoride', there are no studies (I could find about) leachate BPA affects soils other than the FDA saying it is BELOW the amount THEY worry about for our health, I sure hope you get a proper soil test. What a mess of chemistry and who knows what the reactions of all these chemicals become when mixed?
Please get some soil tests and please let us know what you find! Send us the report. Tell the testers what it is you are concerned about finding in your soil. How long ago did you purchase this home?
If you are able to chose another spot, I would do so. You have no idea what they dumped in that area; paints, paint thinner, asbestos, lead debris, old pressure treated lumber, pesticides they needed to dump...all kinds of poisonous chemistry were probably dumped...but perhaps just plastic and nylons? I'd find another spot AND get soil tests done. What water are you using? Well water? From an aquifer below this little dump? There are ramifications of non disclosure with real estate purchases.
Hate to be a downer but you sound knowledgeable and wondering about safety and chemistry of stuff you grow and the water you drink. Rightfully so!