The results of a Life Cycle Assessment (LCA) reflect the full environmental impact of a product or process. These results are divided into various impact categories, each describing a specific type of environmental impact. In this article, we explain more about the impact category Human Toxicity (cancer)—what it means and how to interpret the results.
Context: what are impact categories in an LCA report?
When we perform an LCA, we calculate the complete and precise environmental impact of a product or process. This total impact is broken down into multiple impact categories, such as Climate Change, Land Use, Ecotoxicity, and Human Toxicity. In total, an LCA can include between 15 and 30 categories, depending on the method used.
Each category has its own indicator that helps make the environmental impact measurable. Human Toxicity (cancer) is typically expressed in kilograms of 1,4-dichlorobenzene equivalents (kg 1,4-DCB-eq), which quantifies the harmful effects of toxic substances on human health.
Would you like to learn more about the different environmental impact categories? Read our article on this topic.
What does the Human Toxicity (cancer) impact category measure?
The Human Toxicity (cancer) impact category describes the release of toxic substances during the life cycle of a product or process that may contribute to the development of cancer. These are emissions to air, soil, or water that have direct or indirect harmful effects on human health.
Key sources of carcinogenic substances include:
- Industrial emissions, such as heavy metals (e.g. cadmium, chromium VI, arsenic) and dioxins
- Vehicle exhaust, especially polycyclic aromatic hydrocarbons (PAHs)
- Agricultural chemicals, such as pesticides and herbicides
- Combustion processes, which release toxic substances into the atmosphere
How is the environmental impact calculated in the Human Toxicity (cancer) category?
The environmental impact in this category is calculated by weighing the emissions of carcinogenic substances based on their toxicity and their potential to affect human health.
It's important to note that LCA results for this category do not refer to direct emissions during the use phase of a product. We are often asked whether this impact category reflects the health risks of using products such as electronics in daily life—but that is not the case.
The results for Human Toxicity (cancer) mainly stem from emissions within the supply chain, such as during the production of components, raw material extraction, or transportation. The impact is calculated using LCA databases and characterisation factors that estimate which substances are released during the life cycle and how toxic they are to humans.
This category therefore helps to identify the indirect health impact caused by a product’s supply chain—even when these effects are not visible in the final product itself.
What falls under the Human Toxicity (cancer) impact category?
This impact category can be further divided into three subcategories. The first is:
1. Human Toxicity – Airborne Emissions
This subcategory focuses on emissions released into the air that pose a risk to human health through inhalation. Examples include:
- Fine particulate matter and combustion gases containing toxic substances
- VOCs (Volatile Organic Compounds), such as benzene and formaldehyde
- Industrial emissions of heavy metals and dioxins
2. Human Toxicity – Waterborne Emissions
This subcategory focuses on toxic substances that enter water systems and may impact public health through drinking water or food chains. Examples include:
- Leakage of heavy metals into rivers and lakes
- Pharmaceutical residues and chemical pollutants in drinking water sources
- Toxic substances that persist in the environment and accumulate in plants and animals within aquatic ecosystems
3. Human Toxicity – Soil Contamination
This category addresses chemical contamination of soil, which can pose risks to human health through direct contact or uptake via food crops. Examples of sources in this subcategory include:
- Pesticides and herbicides used in agriculture
- Leakage of heavy metals and toxic substances at landfill sites
- PFAS chemicals that remain in the soil and are difficult to break down
Why is this impact category relevant?
By gaining insight into your impact in the Human Toxicity (cancer) category, your organisation can develop targeted strategies to reduce exposure to toxic substances. This enables more sustainable operations and supports efforts to reduce harm to human health throughout the value chain.
What can you do with the insights from this impact category?
By understanding your impact in the Human Toxicity (cancer) category, you can develop strategies to reduce your company’s contribution to toxic exposure—and operate more sustainably as a result.
Optimising business processes
An LCA reveals which raw materials and processes contribute most to the emission of carcinogenic substances. Based on these insights, you can:
- Switch to less harmful chemicals in your production processes
- Implement improved filtration and air purification systems to reduce toxic emissions
- Lower emissions by using more sustainable materials and production methods
- Choose environmentally friendly alternatives to pesticides and solvents
- Apply sustainable waste management to prevent soil and water contamination
- Design circular production chains that avoid the use of harmful substances
Regulatory compliance
Many environmental regulations impose strict limits on toxic emissions. Insights from an LCA report can help you:
- Monitor and comply with emission limits
- Identify problematic substances and implement targeted improvements
- Obtain environmental certifications and meet international standards
The Human Toxicity (cancer) impact category in an LCA helps you understand the effects of toxic emissions on public health. These insights can be used to reduce emissions, improve sustainability across operations, and meet regulatory requirements.
Want to know how your product performs in the Human Toxicity (cancer) category—and what steps you can take to reduce your impact? Feel free to contact us!
