Health and safety in farms

Introduction

Exposure to hazardous chemicals or other substances, e.g. to pesticides, veterinary medicines (including sheep dips), dusts, fumes or materials such as slurry, sewage sludge or fertilisers; inhaling dusts created when moving grain, fertilisers, straw, hay; contacting slurry, manure, etc; or being splashed with pesticide or sheep dip can all cause ill health.

The accompanying image (right) shows a slurry pit, into which drains excrement from the livestock, e.g. cattle. Needless to say this can be offensive in its smell and appearance.

But there is more to it than that ... the resultant gases include Hydrogen Sulphide - which is highly toxic and which has resulted in fatal poisonings. (Indeed Hydrogen Sulphide H₂S is arguably as toxic as Hydrogen Cyanide HCN.)

Hydrogen Sulphide is very foul smelling but very quickly paralyses the sense of smell and can go on to overcome the victim and eventually cause death.

Biological hazards

Biological hazards range from zoonoses such as ovine chlamydioisis to those associated with animal carcasses which have not been adequately disposed of...

Assessing Risks

Having identified the hazards, some of which are exemplified above, risks need to be assessed, based on factors such as the frequency and manner in which a task is undertaken, etc.

Special measurements may need to be made. For example, risk assessment in an intensive pig breeding farm might need to include measuring Ammonia (NH3) in the air (from decomposition of pigs' by-products) or measuring ambient noise levels (inside sheds full of squealing piglets).

Reducing/Controlling Risks Elimination

Barns or sheds in farms typically contain corners/shelves/spaces underneath tables that are stacked full of chemicals of various sorts. A careful review may identify a number which can be disposed of (following appropriate precautions) and thus eliminating risk altogether.

In this farm, the farmer has decided to reduce the risks of intoxication that may be associated with sheep dipping by substitution -the canister on the left and box cover in the middle relate to an insecticide containing pyrethroids rather than organophosphates. The acute effects of organophosphates are well recognised. Essentially over exposure to these agents can result in damage at the site of transmission of impulses at 'synapses' the junction between one nerve cell and another cell. Organophosphates poison the enzyme which removes an important neuro transmitter (acetyl choline) once it has served its purpose. Therefore as a result of organophosphate poisoning the neurotransmitter continues to cause unchecked stimulation and this may lead to many symptoms such as difficulty with breathing, etc.

Chronic consequences of organophosphate exposure are the subject of considerable current debate. One of the practical problems relating to exposure to chemicals such as these is that in the context of sheep-dipping or agricultural spraying in conditions ranging from wet and windy to hot and sunny, it may be very difficult to control exposure through work practices and personal protection.

The hazards and risks associated with the substituting chemicals or with other chemicals also need to be considered - note the formaldehyde used to treat certain conditions of the feet of sheep.

Further information on health and safety in the agricultural industry can be found at the Health and Safety Executive.