Hi all I have been asked by a client to produce a risk assessment for working in soil contaminated with soluable sulphates. Can anyone direct to me somewhere which would give me some guidance on associated hazards please? This is the first time I have come across this so any help would be appreciated!!

Soluble sulphates are a risk to concrete and not particularly to health. PPE and normal hygiene should be enough. It causes concrete cancer and can in extreme cases drastically affect its strength. Reinforced concrete is particularly at risk it not protected. Soluble sulphates are basically salts

There are soluble sulphates in drinking water. Your site investigation should give you the concentrate of soluble sulphates/sulphates present and guide you on the risk to health. If they are in such a high concentration that they pose a health risk then ground remediation should be recommended in the site investigation report. I have never had a health issue with soluble sulphates.

There's soluble sulphate in the water that comes out of your tap (my water company claims the allowable limit is 250 mg/l, which would be categorised as moderate exposure for concrete if it occurred in the ground). Seawater contains about 2700 mg/l, according to http://www.who.int/water...wq/chemicals/sulfate.pdf . That's a severe exposure for concrete, but would you expect a risk assessment to worry about nausea and irritation to respiratory systems for anyone that goes paddling in the sea? That same document thinks that if you drink nothing but water with sulphate concentrations at a 1000mg/litre level, you'll experience a slight laxative effect, but apparently no other ill effects. So I guess that if your site has sulphates above that level you should advise the operatives not to drink exclusively from the puddles around the site. I don't recall any concerns about risk to health of workers from the sulphates in ground water even where there have been concerns about the concrete.

Thanks for the input. The soil report simply says soluble sulphates in soil (Sulphate Aqueous Extract as SO4). It doesn't distinguish any cations (new work for the day!). This is where I have been having difficulty. From everything I have researched, the WHO (World Health Organisation) - and American equivalents interestingly... - all say that sulphates should not exceed 250mg/l. Studies show that exceeding these limits can cause the 3 things listed in post #8. To be honest, this contractor has gone way way over the top with the paperwork he wants, I am happy to put a risk assessment together for this, but will point out to him the very low levels associated to this activity since it only causes the above mentioned if consumed in water... He also wanted a method statement for it, but I'm drawing the line there.... Thanks again for the input.

I'm pretty sure all water everywhere outside a lab or RO plant has detectable levels of sulphate ions (including, as noted, the drinking water coming out of the tap). I think the first step is to determine what the level is - if it's (say) 20 mg/l that's less than my tap water and you can probably find better things to invest effort in. I think taking the approach that if there's a safe level of something there's likely to be a dangerous level of something else unreported will drive you mad. That reasoning would suggest that all water everywhere (except the RO plant) is likely to kill you.