Author: Valentina Quintero Santofimio

Workplace exposures in low- and middle-income countries: filling in the gaps

Workplace exposures

Adequate control of harmful work exposures should be a universal priority. However, its execution varies widely across the world. These exposures can significantly impact workers’ health leading to disease and mortality. Our recent review on occupational exposures in low- and middle-income countries (LMICs) explores the levels reported across different industries in different countries.

We searched available literature and identified the publications that reported measured exposure levels to occupational agents across multiple industries in LMICs.

What did we find?

Brief summary

We found a total of 58 publications reporting quantitative exposure levels between 1998 to 2022. The countries with greatest number of publications were China, followed by Iran and Tanzania. The most common industries were manufacturing, mining, and agriculture with factory workers and miners being the most common job titles.

Occupational exposures and their levels in this review

Why does this matter?

  • High exposure, limited regulation: Workers in LMICs face high exposure to harmful agents like dust, gases, metals, and pesticides. Compared to high-income countries, regulatory frameworks in LMICs may be underdeveloped, contributing to health risks.
  • Industries at risk: Manufacturing, mining, and agriculture dominate the studies reviewed, with factory workers and miners being the most common occupations. Emerging industries like e-waste recycling present emerging challenges, often in unregulated settings.
  • Sex disparities: Most studies focused on male workers, and therefore little data is available on female-dominated sectors, like informal cottage industries, which remain under-researched despite high exposure risks.
  • Important research needs: The review highlights uneven data availability across regions and industries. It emphasises the need for accurate report of exposure measurements that can contribute to tailored tools, such as job-exposure matrices, to better adapted to LMICs to assess and mitigate the risk of occupational exposures.

Take home message

Occupational exposures significantly contribute to global disease burdens, especially in LMICs where protective measures may be scarce. Addressing these gaps help to mitigate adverse health outcomes resulting from high exposure levels in working populations in developing countries.

The findings of this study were published in the peer-reviewed journal PLOS Global Public Health. The article can be freely accessed and read here: https://doi.org/10.1371/journal.pgph.0003888 

Unmasking the threat of small airways obstruction

Tiny Airways, Big Impact

The damage of the small airways of the lungs can result in inflammation, structural changes, and increased airway resistance. This is a common characteristic of chronic respiratory diseases such as asthma or chronic obstructive pulmonary disease (COPD). While the small airways of the lungs may not be the star of the show, they are a crucial part of the lung health story.

Spirometry: The Lung Detective

Small airways obstruction (SAO) can be detected using spirometry. Traditionally, the mean forced expiratory flow rate between 25% and 75% of the forced vital capacity (FEF25-75) is the preferred parameter. However, novel parameters such as the forced expiratory volume in 3 seconds as a ratio of the forced expiratory volume in 6 seconds (FEV3/FEV6), have proven effective at detecting SAO.

We know that chronic respiratory diseases are leading causes of mortality around the world. Can SAO, even without ticking all the boxes for a doctor diagnosis of respiratory disease, predict death?

The big UK Biobank Study: What did we find?

We analysed the data of over 250,000 participants from the UK, who had high quality spirometry, and found some novel results:

  • About 24% of participants had SAO. Among these, about 10% had isolated SAO, meaning their small airways were obstructed, but their larger airways were not.
  • People with SAO had increased risk of death from all causes, including respiratory diseases, cardiovascular diseases, and cancers. The risk was especially high for respiratory diseases, with more than double compared to those without SAO.
  • Even without respiratory disease (isolated SAO), the mortality risk was increased for cardiovascular diseases and cancers. Importantly, these findings were also true among people who have never smoked, indicating that SAO itself, regardless of smoking, is a critical factor.

Why should we care?

  1. Early Detection: Catching SAO early could be crucial in preventing more severe lung diseases later in life.
  2. Lifestyle Factors: Smoking is a big no-no for lung health, but even people who have never smoked can have SAO. This is likely to be caused by other factors.

While the UK Biobank cohort’s lack of representativeness and the relatively short follow-up period pose limitations, the study’s large sample size adds significant weight to the findings. Future research should aim to replicate these results in more diverse populations and explore the underlying mechanisms linking SAO to increased mortality.

Take home message.

Understanding and detecting SAO can give us a head start in managing chronic respiratory diseases such as COPD and asthma. Ultimately, this can aid to reduce respiratory morbidity worldwide. The findings of this study were published in the peer-reviewed journal CHEST. The article can be freely accessed and read here: https://doi.org/10.1016/j.chest.2024.04.016