soil testing

[potato girl]

good evening
please can any one help i had some soil samples done as there might have been lead on my land but i do not understand the results.
the results are

lead
<0.7mg/kg....sample1 224

thanks in advance

[veggiechicken]

Hello potato girl and welcome to the Forum.
I'm sorry but I haven't a clue what your results mean but I wanted to say Hello in case you thought you were being ignored.

[Bren In Pots]

Hello potato girl
I had a look on Google but just ended up being confused so hopefully someone will come along who knows the answer.

[Snadger]

good evening
please can any one help i had some soil samples done as there might have been lead on my land but i do not understand the results.
the results are

lead
<0.7mg/kg....sample1 224

thanks in advance

We had some soil samples done on allotment sites in Newcastle area. It was either measured in Parts per Millliom (PPM) or Mg/Kg.

The standard for Lead was 100. Our site was 281! One site had 1066.

I would say that yours was very low at 0.7 unless the 224 was the PPM figure, which would make it much the same as our site.

[piskieinboots]

I can't see the image on the iPad, but even I could it would be like trying to read Mandarin. Thankfully, Snadger comes good

Welcome to the Vine.

[Cadalot]

Ok here is a link to some guidance http://geosmartinfo.co.uk/wp-content...k-Guidance.pdf

Basically there are agreed levels for what will not do harm to humans and wildlife and the report you have should inform you of those limits

You state

lead
<0.7mg/kg....sample1 224

So is the limit for humans appears to be less than 0.7mg/kg an is the 224 figure the result from the test and is it also mg/kg. ? without seeing the report it's hard to be specific, but I would go back to the company that tested the soil for you and simply ask them, they may even have a guidance document they can send you.

I used to get contamination surveys for building projects, to establish what remediation action needed to be done if any.

[Jungle Jane]

It looks like the sample tested was 224,this link mentions 300ppb being ok;
"Generally, it has been considered safe to use garden produce grown in soils with total Pb levels less than 300 ppm. The risk of Pb poisoning through the food chain increases as the soil Pb level rises above this concentration. Even at soil levels above 300 ppm, most of the risk is from Pb contaminated soil or dust deposits on the plants rather than from uptake of Pb by the plant."
It's on page 19
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3648544/

[Jay-ell]

Isn't 1kg = 1000000mg so mg/kg and ppm should be the same.

Of has my maths gone

[Jungle Jane]

Is the <0.7mg/kg just the amount of soil they took for testing (less than 0.7mg/kg) ?

[Jay-ell]

Soil testing uses a specific amount of soil. That way they can measure how much of a substance is there and extrapolate the ppm or mg/kg value. Each test has certain minimum levels they can detect and limits to their accuracy which is possibly the <0.7mg/kg the 224 could be the measured amount in mg/kg or ppm.

No Column headers or "what this means" sheet with the results?

[Snadger]

Give that man a coconut!

Isn't 1kg = 1000000mg so mg/kg and ppm should be the same.

Of has my maths gone

Good thinking Jay-ell! Thats why my allotment report says Mg/Kg OR ppm to designate you can read it either way for all elements and the readinngs can be expressed as mg/Kg or ppm.

[Snadger]

I would publish a copy of my report but I was given it in strictest confidence from someone who is putting in a claim against the Council!

[Potstubsdustbins]

That result is very confusing to me. 0.7mg per kg is actually 7000 parts per million a very unlikely result unless there used to be a lead smelter near by. If the 224 means ppm that would be much more realistic in the UK.

DEFRA say that up to 300ppm is fine and even over that level the main problem would be dust on the plants or in the air.

Lead is a strange type of toxin but is at it's most dangerous when a dust or a gas with gas being the worst case. However to get it to change to a gaseous state you have to boil it no mean feat and certainly something a gardener wouldn't have to worry about. I was told as an apprentice that if the melting pot we used to heat lead for wipe joints ever went cherry red and bubbled turn the heat source off and run.

Breathed in as an air born dust it will be slowly absorbed into the body and it is a long process to get those levels back down to normal.

Having said all that I do believe like a lot of thing these days the dangers are over played somewhat, I have worked with lead since the age of 15 and so far as I know have not suffered any bad effects.

A for instance is the ban on solders containing lead and the use of lead pipe in new installations for potable water. Great in theory but people seem to forget the thousands of miles of Victorian lead water services that are still in use today.

[Jay-ell]

That result is very confusing to me. 0.7mg per kg is actually 7000 parts per million .

Nope. 1kg is 1000 grams, 1 gram is 1000 mg
1000 x 1000 = 1000000 or 1 million

So 0.7mg/kg IS 0.7ppm

7g is 7000ppm

[Potstubsdustbins]

^^^^^I am not sure which one of us has the decimal point in the wrong place.

1,000,000 mg per kilo we both agree on that.

1,000,000 divided x 100 = 10,000 or 1% 7 tenths of that is surely 7,000.

Try .7 x 1,000,000 = 700,000.

This is doing what is left of my brain in that's for sure