Phoenix Journal · LEV & Air Quality
Waste and recycling sites deal in a hazard you can smell but not see. Bioaerosols, the airborne bacteria, fungal spores and endotoxin released whenever organic waste is handled, are a recognised cause of lung disease in the trade.
Recycling and waste sites deal in a hazard that does not show up as a plume or a dust cloud: bioaerosols. These are airborne biological particles, chiefly bacteria, fungal spores such as Aspergillus fumigatus, and endotoxin from the cell walls of certain bacteria, thrown into the air whenever organic waste is tipped, shredded, screened or turned. The rotting smell is a clue that they are present, but the particles themselves are invisible and are breathed in without the operator noticing.
The health effects fall mainly on the lungs. Exposure to bioaerosols in the waste sector is linked to respiratory illness including occupational asthma, inflammation and irritation of the airways, chronic bronchitis and reduced lung function, along with eye irritation and, at times, gastro-intestinal upset. Waste and recycling workers report more work-related respiratory symptoms than most other occupational groups, and the aerobic composting of organic waste is particularly associated with these effects. On top of the allergic and irritant response, Aspergillus fumigatus can cause infection in people whose immunity is weakened or who already have a lung condition, which widens who is at risk beyond the obviously exposed.
The exposures are highest exactly where the handling is roughest: waste reception, debagging, shredding, screening and the turning of active compost. Even the cab air on loading machines is often more contaminated than the air outside, which tells you how readily these particles travel once they are airborne. Studies of compost workers have measured raised upper-airway inflammation across a single shift, a sign the dose is landing even when nobody feels acutely ill.
No limit, which changes the job
Britain sets no occupational exposure limit for bioaerosols, and that absence shapes how the risk has to be managed. Without a figure to test against, COSHH still applies in full, so the duty holder must assess the risk and control exposure to as low a level as is reasonably practicable, judged by good practice rather than by a reading. Other countries have proposed values, with the Netherlands suggesting a limit for airborne endotoxin and Germany a control value for mould, but none of these is law here.
The lack of a threshold is not reassuring; it reflects that no safe level has been established, and there is a dose-response relationship, meaning the processes that throw up the most bioaerosol are the most likely to cause harm. That points the control effort at the dustiest, most agitating steps rather than spreading it thinly across the site. It is not only open-windrow composting that carries the risk: materials recovery facilities and mechanical biological treatment plants generate bioaerosol wherever mixed waste is broken open and sorted, so the same duty applies indoors. Environmental permits reinforce the point from the community side, typically requiring bioaerosol levels to fall back to background within 250 metres of the site boundary.
Because you cannot prove safety with a number, control rests on design and routine: enclosing and extracting the dustiest processes, keeping the site clean and damp enough to stop dust lifting, filtering the air in machine cabs, and backing all of it with respiratory protection and strict hygiene. Endotoxin in particular can trigger fever-like and inflammatory reactions, so even brief peaks during debagging or turning are worth designing out rather than tolerating.
Protection you can rely on
With no engineering fix that fully removes airborne spores from open-air handling, respiratory protection carries real weight on waste and compost sites, and the HSE recommends it for compost workers. But RPE only works if it is the right type for the hazard, worn correctly and sealed to the wearer's face, which is why getting respiratory protective equipment, getting it right is a discipline rather than a purchase. A mask handed out without fit testing or maintenance offers a false sense of safety on exactly the sites where the exposure is hardest to see. RPE is the backstop, not the first move: enclosing picking cabins and shredders and putting sorting cabins under filtered, positive-pressure air removes far more exposure than any mask, and should come first wherever the process can be enclosed.
Catching harm early
Because bioaerosol illness builds slowly and quietly, health surveillance matters: a respiratory questionnaire and lung-function checks can catch a decline while it can still be acted on, which is the whole purpose of building a health surveillance programme. Alongside it sit the unglamorous basics that do most of the work, from keeping compost at a moisture content that suppresses dust, generally around 50 to 60 per cent, to cleaning up spillages, filtering cab air, and enforcing hygiene so that workers wash before eating and do not carry contamination hand to mouth. None of it is high-tech, but together it is what keeps an invisible hazard from becoming a chronic one.
Questions
They are airborne biological particles, including bacteria, fungal spores such as Aspergillus fumigatus, and endotoxin from bacterial cell walls, released when organic waste is tipped, shredded, screened or turned. They are invisible but can cause respiratory illness when inhaled.
No. Britain sets no occupational exposure limit for bioaerosols, so COSHH requires the duty holder to assess the risk and control exposure as low as reasonably practicable. Other countries have only proposed values.
Enclose and extract the dustiest processes, keep the site clean and damp enough to stop dust lifting, filter cab air, and provide well-fitted respiratory protection with good hygiene. Health surveillance catches early respiratory changes.
Phoenix Duct Clean · by the numbers
Extraction on picking cabins, shredders and enclosures needs testing to prove it captures, not just moves air. Phoenix examines and tests LEV to COSHH Regulation 9. UK-wide.