Blood Tests


Please note that you can have a breath test but there is a school of thought that this is less accurate than a blood test. However, recently we have been informed that a breath test, done properly is more accurate.

Why have any test? The reasons are many and varied. These are just some of them.

  • In order that your GP has proof of what is wrong and doesn’t treat you for something else, which may not be what is wrong anyway and according to some of the victims we have spoken, will do harm.
  • To prove to your employer, partner etc that you haven’t been imagining things.
  • To prove a legal case. Even if you don’t want to sue now, you may change your mind later and if you don’t obtain a test now, it will be too late later. Please bear in mind that if you have been poisoned this will affect your higher intellectual functions so this is really not the time to make a once and for all decision.

A. Carbon Monoxide (CO) – Time is of the essence It is vitally important to have a blood test as soon as possible after exposure, i.e within minutes or hours. Your GP should be able to arrange this free for you. If days have already elapsed since exposure we suggest you proceed straight to B below or seek tests on the appliances if they have not already been altered or changed. From our many years of experience, we find that many GPs do not undertake this test quickly enough or at all. Our advice therefore is to contact your GP but also, in addition to seriously consider contacting MediChecks (see below). In our opinion, two tests are better than one. The only downside is the cost, which is about £149 for a test for carbon monoxide poisoning. It may be that by the time you have blood tested the CO will have disappeared from your blood. It is very difficult to advise whether it is worth paying or not. It depends on time elapsed since exposure, oxygen given, amount and length of exposure to CO and individual constitution. However, you will only have one chance to obtain a positive test. Please note that even if the blood test is negative, this result does not prove an absence of carbon monoxide, i.e. it is still possible that something in your home or car or at work etc. is emitting carbon monoxide. Please note that we have experienced people who have had a blood test, which for whatever reason (e.g. delay, oxygen treatment etc.) turns out to be negative, yet their appliances, when tested are found to be emitting dangerous levels of CO.

B. BLOOD or URINE TESTS FOR OTHER PRODUCTS OF COMBUSTION Why have a test for other products of combustion? Do visit This is a DEFRA document (i.e. a British Government document). See also For details of other toxins found in Natural Gas combustion and  for details of other toxins found in Domestic Heating Oil (Kerosene) combustion. This is from the United States Environmental Protection Agency. You will see from these documents, that in addition to carbon monoxide, there are many other toxic substances, in the products of combustion from any carbon based fuel, that are emitted alongside CO, which may have serious consequences for your long-term health. Tests for these should also be undertaken as soon as possible but unlike CO, there is no need for an immediate test. The recommendation is that tests should be undertaken within a month or two but if you are going to pay for these tests, then to make sure of an accurate result, CO-Gas Safety advises you make do this within days or a week or two at most. However, people have had tests after months or even years and some toxins have been found. Of course the later the tests are done the easier it will be to assert that the toxins came from a source other than a fumes event on a particular appliance at a particular time. Again, do ask your GP if all or any of these tests could be done under the NHS.


Blood tests could be done but Gareth Hughes now considers that urine tests before and after a provoking agent would be more accurate. These can be carried out in the States by or see   This apparently costs around £120 and tests for all toxic metals. Dipika Joshi Tel/Fax. 07828249967. Mob. 07961 174217 website can assist in this country with regard to the kit needed. She is clinical pharmacist, functional medicine (treating the person as an individual) and her husband is a pharmacist. Of course it may be that such evidence is not given much weight in a court of law and it is worth asking your legal representatives about this before you spend money on these tests. It is also worth asking your medical advisers if use of the provoking agents could do you harm. There are basically two types of test.

  1. Heavy metals

For example; Mercury, Lead, Arsenic, etc Cost about £299. See further Please note that Medichecks state that a patient cannot use the results of these tests in court. We find that an odd condition of the contract and it may be that you will wish to break the terms of your contract and use them anyway. However, the court is not likely to give such tests much weight. It may be that you want to go ahead anyway. This is your decision to make. An alternative is to go back to your GP and keep asking for an NHS test. It is the heavy metals that are more likely to still remain in your blood.

  1. Volatile organic compound screen. For example; Benzene, Toluene, etc.

Medichecks no longer does this. We are trying to locate another lab but apparently there is no lab in the UK which does this. For more details and up to date costs do contact MediChecks or visit their website

  • Contact MediChecks by telephone, 08456 029029. This is answered 24/7. They are open 9am-5pm Mon-Fri. Blood samples in London can be taken 8am-7pm Mon-Fri and 9am-1pm Saturdays. Outside London 9am-3pm Mon-Fri. This sample should preferably be taken as soon as possible on the day of exposure or if exposure is in the evening, contact should be made immediately the following morning.
  • Upon receiving your details (name, address, date of birth, telephone, email, payment details, exposure date) MediChecks will immediately arrange an appointment for the blood samples to be taken. If you reside outside the London area or can not travel to their laboratory on Wimpole Street in London, they will *arrange for the samples to be drawn the following day at a local GP surgery or hospital.
  • Once the appointment has been arranged they will contact you by telephone to confirm this.
  • Payment for the test (£149) will be taken and the test kit sent out by Guaranteed Next Day Delivery before 9am.
  • After your blood sample has been taken, it should be posted to the laboratory (unless sample is taken at the lab). CO-Gas Safety recommends using special delivery.
  • Within 3 working days you will be contacted by a Nurse advisor, who will inform you of the result and give any necessary advice.
  • Results will then be posted or uploaded onto MediChecks’ secure servers.
  • However, if you want to rely on the results for a legal case, it is advisable to visit their laboratory with your passport to prove identity and have the blood taken there. Ask your legal representative about this before you arrange any tests.
  • The availability of appointments outside the London area is not guaranteed. It may be dependant on geographical location. No payment will be taken by MediCheck until an appointment has been confirmed.

Please note MediCheck has kindly offered us a special rate but CO-Gas Safety is not receiving any payment for this recommendation. If anyone knows of any other testing laboratories who offer such a service do please let us know on and we will consider putting them on our website too. An alternative is:- Blue Horizon Medicals.

  1. Cost of a simple Carboxyhaemoglobin test at a Spire Hospital in the UK through is currently £121.15 – Use coupon code “ cogas “ when is in the basket for a £70 discount. We use 30 Spire Hospitals across the country for this.
  1. Cost of a simple Carboxyhaemoglobin test in London though is currently £119.25 – Use coupon code “ cogas “ when is in the basket for a £60 discount.
  1. Trace Metal in Blood Test in London or nationally – though is currently £215.25 – Use coupon code “ cogasmetal “ when is in the basket for a £30 discount. The same test is available as a postal pathology kit (let us help you find someone to take your blood) through  – direct link

  Paul Harris Founder Harley Street Health Checks UK Ltd   For further information about other products of combustion and toxins visit November 2014 Updated April 2018