Both the detritus from house dust mites and mould spores are potent airborne allergens.

Exposure to high concentrations of these allergens over a prolonged period will cause sensitisation of atopic individuals (those with a predetermined genetic tendency to sensitisation), and may sensitise non-atopic individuals. Once a person is sensitised relatively low concentrations of the airborne allergen can trigger allergic symptoms such as rhinitis, conjunctivitis, eczema, cough and wheeze.

For a sensitised person, repeated exposure can lead to asthma, and it appears that the severity of the asthma intensifies with increasing humidity, house dust mite and mould levels.

The inhalation of asbestos fibres can cause pleural disease (pleural plaques and fibrosis), lung cancer and mesothelioma (cancer of the pleura, the lining around the lung, or, less frequently, cancer of the peritoneum).

Each of these conditions typically occurs decades after first exposure to asbestos.

Pleural plaques may occur ten years after asbestos exposure, although they are likely to go unidentified. Lung cancer and mesothelioma typically occur 20 to 50 years after exposure.

Lung cancer has very poor survival rates, and there is no known cure for mesothelioma.

Lack of space and overcrowded conditions have been linked to a number of health outcomes, including psychological distress and mental disorders, especially those associated with a lack of privacy and childhood development.

Crowding can result in an increased in heart rate, increased perspiration, reduction of tolerance, and a reduction of the ability to concentrate. Crowded conditions are also linked with increased hygiene risks, an increased risk of accidents, and spread of contagious disease.

The health conditions which can be caused by inadequate light include:

a)  Depression and psychological effects caused by a lack of natural light or the lack of a window with a view.

b)  Disturbance by intrusive artificial external lighting at night.

c)  Eye strain from glare and a lack of adequate light (natural or artificial).

d)  Flicker caused by certain types of artificial light causes discomfort and may cause photo convulsive reactions to those susceptible.

The elderly and those with impaired vision are more likely to be unable to detect potential hazards, where there is inadequate or excessive light.

In addition, the vision of the elderly is slow to adjust to changes in light levels.

Foods (and liquids such as milk) can become a source of food poisoning through contamination, the multiplication of micro-organisms through poor or inappropriate storage, or through inadequate cooking.

llnesses resulting from food poisoning range from mild stomach upset through to death from infectious gastro-intestinal disease, or hospital admission because of severe diarrhoea, vomiting and dehydration. However, the majority of mild gastro-intestinal infections which result from food poisoning go unreported (and so are not included in the statistical evidence).

 

It is estimated that in the general UK population there are 86,000 cases of food poisoning annually.

It is estimated that at least 50% of these cases arise in the home, with some estimates putting the figure even higher – 86% for Salmonella and 97% for Campylobacter.

In the UK, the main threats to health from water result from contamination.

Microbiological pathogens which affect drinking water typically cause gastro-intestinal illness. Campylobacter and Cryptosporidium are the most common causes of gastro- intestinal illness associated with drinking water.

Legionella, which typically causes respiratory infection, also presents an infection risk from domestic water systems.

Young children and the immuno-compromised are most at risk from ingested pathogens, and the elderly and immuno-compromised are most at risk from Legionella.

Contamination by radon and lead are dealt with separately.

 

The quality of water supplied from public mains is outside the HHSRS assessment and is subject to separate controls.

Biocides are intended to prevent growth or development of insects, fungi, moulds and bacteria, or kill those already present. The potential for harm to human health varies depending on the particular biocide.

The main health risk is from inhalation, although skin contact and ingestion may also be an issue, particularly for small children.

Continual exposure at low levels has been shown to cause mental retardation and behavioural problems in children.

Lead is readily absorbed from the intestinal tract, especially in children, and its absorption is enhanced by dietary deficiency of iron and calcium. There are around 100 cases a year of acute lead poisoning, most of which are attributed to ingestion
of lead from paint.

There are up to about 10 fatalities each year result from lead poisoning. However, the most prevalent risk is Intelligence Quotient (IQ) deficiency in children, rather than acute poisoning. Even with relatively low levels of lead in blood, there are indications that it affects the IQ of children.

 

Potential effects are:

 

a)  the fear of a possible burglary occurrence or recurrence;

 

b)  the stress and anguish caused by a burglary; and

 

c)  injuries caused to occupants by an intruder (aggravated burglary).

 

 

The most common harm suffered as a result of burglary, or fear of burglary, is emotional stress, with 28% of victims being affected “very much”, 31% “quite a lot”, and 24% “just a little”37.

The emotional impact is greater for burglaries where there is successful entry to the dwelling.

Psychological disturbances and physiological changes resulting from annoyance and sleep disturbance.

Typical health effects are stress responses, sleep disorders and lack of concentration. Headaches, anxiety and irritability are also associated with noise induced stress, and the effects of sleep disturbance may affect mood the following day.

Extreme psychological outcomes include suicide, and assault due to aggravation over noise. However, hearing loss and impairment caused by noise in dwellings is unlikely.

Insect pests can cause allergic reactions. Children who live in dwellings visibly infested with cockroaches show high levels of sensitivity to cockroach allergen.

Contact with cockroaches can cause dermatitis, uticaria, rhinitis, bronchitis and asthma. Some people have an aversion to cockroaches amounting to a phobia and can suffer anxiety when in the presence of the insects.

Insects are also responsible for food spoilage, rendering it unpalatable if not inedible. Insect pests, including flies and cockroaches, are known to be mechanical vectors of diseases, picking up disease causing organisms on their bodies from one source and transferring it. Their behaviour means that they travel from matter such as rotting garbage and animal fæces that are infected to food intended for human consumption.

Rats and mice are known to be infected with pathogenic organisms. Rats have been found to be infected with such zoonotic agents as Yersinia entercolitica (Yersiniosis),Listeria spp (Listeriosis), Cryptosporidium parvum (Cryptosporidiosis), Toxoplasma gondii (Toxoplasmosis), Leptospira spp (Leptospiral Jaundice or Weil’s disease),Trichinella spiralis and Trichuris spp (Whipworm infection).

Birds, such as pigeons, can cause nuisance, carry diseases including Salmonella and can harbour biting insect pests such as the Martin Bug in their nests.

Note that hazards associated with sanitation and drainage, domestic water, personal washing facilities and food safety are each dealt with as separate hazards.

Falls result in physical injury, including: bruising; puncture injuries; fractures; and head, brain and spinal injuries. The nature of injury is in part dependent on the distance of a fall, and in part dependent on the nature of the surface collided with.

Falls from windows, landings and balconies is an important cause of death within the under five age group because the underlying rate of death for children is low. This is one of the more common causes of death for children (and, for that matter, young adults) – the low average hazard scores reflecting the fact that at this age people are unlikely to die, from whatever cause..

 

 

There are around 50 fatal falls from windows in domestic buildings each year, and around 2,300 non-fatal cases treated in hospitals.

There are around 8 fatal domestic balcony falls each year.

The most common cause of death from a fire (around 38%) is being overcome by gas or smoke.

Around 26% of deaths are attributed jointly to both burns and being overcome by gas or smoke, and 25% of deaths are the result of burns alone. 

Although children are more likely to be exposed to fire, the elderly are more than three times as likely to die from a fire, and therefore are more at risk. People over 80 years of age have the highest rate of deaths per million population, and 36% of fire deaths are to people over 65 years of age.