White spirit is a colourless volatile liquid found in many homes and used as a paintbrush cleaner and to remove adhesive residue from surfaces. It is irritant to the skin and mucous membranes, including the gastrointestinal tract. It dries and de-fats the tissues leading to irritation and erythema. Burns may occur from prolonged contact. Petroleum distillates are thought to cause effects on mucous membranes and skin by dissolving lipid membranes and damaging cells. Petroleum distillates can also cause central nervous system (CNS) depression, and although the exact mechanism is unclear, hypoxia is thought to be a contributing factor.
The most severe clinical problems associated with exposure to white spirit are due to aspiration, resulting in severe pulmonary dysfunction and rapid onset hypoxaemia. The risk of aspiration and lung damage is high; white spirit has a low surface tension, low viscosity and high volatility. The surface tension allows widespread diffusion into the lungs even when small quantities of fluid are involved and low viscosity enables deep penetration into the distal airways.
Aspiration causes severe intrapulmonary shunting, which results in hypoxaemia and acidaemia. Studies have shown that aspiration of petroleum distillates results in changes in the surface tension properties of pulmonary surfactant, haemorrhagic necrosis, intra-alveolar oedema, epithelial destruction and inflammatory exudation.
Clinical effects
Breath and hair may smell strongly after exposure to white spirit. Ingestion or oral exposure following grooming after dermal exposure may cause a burning sensation which can manifest as hypersalivation, head shaking and pawing at the mouth. There may be local irritation and ulceration in the mouth, vomiting, diarrhoea and inappetence. Animals may be distressed due to the discomfort, irritation and pain.
Aspiration can occur after ingestion (including grooming) or if vomiting has occurred. Clinical effects include choking, coughing, dyspnoea, cyanosis, pyrexia and in severe cases, pulmonary oedema. There may also be leucocytosis. Signs can progress for the first 24 to 48 hours with recovery over 3 to 10 days. Ingestion of a large volume or inhalation of white spirit (eg following a spill in an enclosed space) could result in CNS depression with ataxia, disorientation, tremor, drowsiness and, in (rare) severe cases, coma. Tremors and convulsions may also occur but are rare.
White spirit on the skin may cause erythema, dermatitis, blisters, alopecia, inflammation and burns. Splashes in the eye may cause conjunctivitis and ocular oedema.
Management
When managing animals with dermal exposure to white spirit, remember that white spirit is flammable, so avoid any sources of ignition. Ensure the area is well ventilated, particularly when handling animals with heavy contamination, to prevent staff becoming unwell.
Use of emetics or gastric lavage after ingestion of white spirit are contraindicated because of the risk of aspiration. An anti-emetic can be given to prevent vomiting and reduce the risk of aspiration. Activated charcoal is not recommended and may increase the risk of vomiting. Sedation is best avoided where practical as it can depress the gag reflex and increase the risk of aspiration. If there is evidence of oral discomfort, it may be helpful to wash the mouth out with water, depending on the clinical condition of the animal. Contaminated eyes should be irrigated with water or saline, stained with fluorescein and examined for corneal injury.
Animals with dermal exposure should be thoroughly washed. Petroleum distillates are not miscible with water so detergents or commercially available hand degreasers should be used. If not available, the use of animal or vegetable fat can be helpful when rubbed into hair and skin before washing with soap and water. A collar to prevent grooming may be required. Mild irritation of the skin will usually respond to an emollient, but a topical steroid may be required for moderate to severe dermatitis and severe irritation should be managed as a thermal burn injury.
After decontamination, treatment is symptomatic and supportive. A bland diet is recommended if there is evidence of severe buccal irritation. In animals with aspiration, pneumonia care will be required because of the risk of pulmonary oedema.
Animals with white spirit exposure should be assessed for respiratory effects. X-ray evidence of pulmonary changes may occur within an hour of aspiration or take 6 to 12 hours to manifest and be maximal at 48 hours. Aspiration should be managed conventionally with oxygen supplementation and cage rest. Routine use of antibiotics is not necessary in animals with aspiration since petroleum distillate pneumonitis is non-bacterial in origin. Steroids are not recommended in these cases since they can increase the risk of infection and have been shown to be ineffective. Salbutamol can be used as a bronchodilator, if required.
Animals that remain asymptomatic for 6 to 12 hours after white spirit exposure are likely to remain well, but animals with pulmonary oedema have a more guarded prognosis.
