Non-infectious environmental hazards: migrant health guide

Advice and guidance on the health needs of migrant patients for healthcare practitioners.

Main messages

Some migrant patients may be at increased risk of illness arising from chemical exposure. This may either be prior to arrival in the UK or in the UK as a result of consumption of imported food or use of traditional medicine or cosmetic products, or associated with household or occupational exposure.

Clinicians should be alert to the possibility of illness having a chemical aetiology and seek expert advice on diagnosis and management.

Primary care practitioners have a role to play in prevention of exposures within the UK through appropriate education of patients about possible risks.


Culture and ethnicity are strongly related to risk factors for exposure to toxic chemicals because of practices and traditions within countries.

Global migration means health problems associated with these exposures will no longer be limited to their country of origin and may increase the number of cases of unintentional poisonings associated with exposure to toxic chemicals seen in the UK.

Early recognition and management of patients at risk of unintentional poisoning, both in primary care and in hospitals, is key to reducing morbidity and mortality and clinicians should recognise the cultural and ethnic factors, which may increase the likelihood of previous, ongoing, or new chemical exposures, in migrants seeking health care.

Previous exposure

Some migrant communities in the UK may be at increased risk of chronic adverse health effects following exposure to toxic chemicals in their home countries which may only become apparent after their arrival into the UK. See non-infectious environmental hazards examples page for more information about:

  • lead poisoning in migrant children
  • arsenic poisoning in Bangladeshi population

Ongoing exposures

Migrants to the UK often retain practices and can continue to use chemicals, such as cosmetics or health remedies, indigenous to their country of origin which may result in unintentional consequences such as poisoning or adverse drug reactions. See non-infectious environmental hazards examples page for more information about:

  • heavy metal poisoning and Ayurvedic medicine
  • heavy metal poisoning and cosmetics
  • adverse drug interactions and traditional medicine
  • chemical contamination of imported food products
  • heavy metal poisoning and geophagy

New exposures

It is also important to recognise that some unintentional poisoning of migrants may occur following new exposures arising in the UK. Exposure to toxic chemicals may occur in domestic settings due to substandard living accommodation or within the occupational setting due to poor working conditions. See non-infectious environmental hazard examples page for more information about:

  • lead poisoning in the home
  • occupational exposure

Patient assessment

Remain vigilant for the possibility of an illness having a chemical or toxicological aetiology, particularly if:

  • the patient’s illness is unusual in any way
  • other diagnoses have been excluded
  • it is unresponsive to treatment

Keep in mind that exposure to a toxic chemical may affect many organ systems.

Exposure and effects can be acute or chronic and the latency period from exposure to manifestation of disease can vary, ranging from immediate to delayed (hours or days) to prolonged (decades).

Take a full clinical and exposure history. This requires only a few minutes and can be abbreviated, expanded, or focused according to the patient’s signs and symptoms. The Agency for Toxic Substances and Disease Registry provides further information about taking an exposure history including the main areas of enquiry to consider.


Seek expert advice from the local poisons information service on a case by case basis for information on suspected poisons or exposures and the laboratory assays that may be required (see resources below).

Only undertake investigations if they are likely to aid diagnosis or influence the management of a patient. Toxicological investigations are likely to be helpful:

  • to assess the severity of poisoning (quantitative analyses)
  • when diagnosis of poisoning is uncertain, particularly in children
  • when administration of an antidote depends on the identification of a poison and its concentration in the blood
  • to monitor the efficacy of an active elimination technique or antidote
  • to determine the prognosis of complications or fatal outcome to poisoning
  • when there is occupational or environmental exposure to chemicals

There are no simple tests able to detect all of the chemicals to which a patient may have been exposed.

Biochemical and physiological tests may indicate the type of chemical involved.

Consider sending environmental samples, for example face creams or tablets, if available.

Urine and blood specimens can be screened for chemicals; safeguard samples against contamination and send immediately in the correct containers to avoid losses.

Contact the relevant local biochemistry laboratory before obtaining biological samples for information on the local testing arrangements, how samples should be collected and where they should be sent for analysis.


Seek expert advice for information on the management of patients that have been exposed to toxic chemicals (see resources below). The treatment of poisonings will depend on the chemical involved. Possible management includes:

  • activated charcoal: sometimes used following acute chemical ingestion to stop further absorption into the blood
  • antidotes: these are substances that either prevent the poison from working or reverse the effects of the poison
  • general supportive measures: may be needed if the patient is agitated, has seizures or stops breathing

Prevention and control

Advise patients to check the labels and ingredients of any cosmetics, medications or supplements they use that are not prescribed by a health professional.

Encourage patients to consult with their GP before commencing any alternative treatment.

It may be difficult to access information about a proposed treatment and to give positive endorsement to any particular medication. You could however describe the general risks of unregulated products to patients.

Consider screening patients with a history of previous or ongoing exposure to toxic chemicals if effective treatment is available.

Resources for health professionals

The PHE chemical hazards compendium is an online resource providing in-depth information on the toxicology of chemicals

TOXBASE can be used in the first instance for general information (requires registration).

National Poisons Information Service (NPIS) can be used when there is insufficient information on TOXBASE, or for atypical presentation, unfamiliar antidotes (and access), problems with tablet identification, or for specific advice on individual cases.

UK Teratology Information Service (UKTIS) provides a national service on all aspects of the toxicity of drugs and chemicals in pregnancy. A telephone advice line is available for health professionals and information is also available online through TOXBASE.

UK Medicines Information (UKMI) service provides general information on medicines including dosing and drug interactions.

Chinese Medicine Advisory Service (ChiMAS) provides use and safety information on Chinese and other traditional herbal medicine to health professionals.

Regional Laboratory for Toxicology performs analysis for a wide range of drugs and intoxicants on body fluids and tissues.

Food Standards Agency (FSA) provides advice on the chemical, radiological and microbiological safety of food.

Patient UK leaflets for health professionals are available on arsenic poisoning and heavy metal poisoning.

Published 31 July 2014