You are not logged in

Shellfish processing: turning 'waste' into 'resource'


The Challenge

The Allergen Monitoring Service at HSE's Science and Research Centre was asked to quantify tropomyosin (TM) in an agricultural compost containing added ground, untreated shell waste from seafood processing. Tropomyosin is a known allergen found in the edible parts of certain shellfish; respiratory exposure to TM can cause allergic sensitisation, respiratory symptoms and occupational asthma. In this case TM was measured at 0.42 ug/g of compost.

Some 50-85% of processed shellfish is 'waste'; estimated as 100,000 tonnes per annum. The agricultural sector has been looking at various ways of turning this 'waste' - expensive to send to landfill - into a 'resource' with value. This case study identifies one route that has been tried, but where there is the possibility that allergen exposure is shifted to a wider worker population.

The Solution

In 2005/2006 HSE funded the development of methods for monitoring airborne levels of the major shellfish allergen, TM, together with a number of site visits. Similar small scale studies were carried out in 2011 and 2017 when further laboratory work clarified the applicability of the TM immunoassay across many edible shellfish species. Limited commercial monitoring by occupational hygienists has also been carried out. In 2020 a collaboration between HSE and the University of Manchester (UoM) identified a 24-fold excess of occupational asthma in the UK seafood processing sector in the period 1992-2017*. The work continues: an HSE-funded research project, led by UoM, is currently underway investigating symptoms and occupational exposure to seafood allergens.

The Outcome

  • A simplistic calculation suggests that activities in the agricultural sector leading to high dust levels of 10 mg/m3 would be associated with airborne TM levels of around 4 ng/m3. This is relatively low compared with airborne TM levels in the UK shellfish processing sector (median 60 ng/m3), although concerns have been raised as to how well COSHH and exposure control are applied across the agricultural sector**.
  • Atmospheric monitoring amongst shellfish processors suggest that significant allergen exposure occurs in that sector.
  • While there may be good agricultural reasons to increase significantly the amount of ground shell in compost, the grinding of such shells to a fine material may itself be a higher-risk activity.
  • Organisations need to consider the regulatory implications of processing shellfish 'waste'. Compost producers chemical manufacturers, fish food producers and even battery manufacturers are using this material.

The law requires organisations to adequately control exposure to materials in the workplace that cause ill health. This is the Control of Substances Hazardous to Health Regulations (COSHH). Harmful substances include any materials or substances used or created at work that could harm your health.

We're pleased to be able to share the results of this study. For more information about our work in this area email the team at

  1. *Mason HJ, Carder M et al. Occupational asthma and its causation in the UK seafood processing sector. Annals of Work Exposure and Health (2020) 64(8) p817-825.
  2. **Median TM value of 60 ng/m3 (IQR 8-286 ng/m3 ) and a 90th percentile of 956 ng/m3, with a strongly right skewed distribution.

Back to the top