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Guided by Science

Prevent Cancer Now advocates for modern laws, policies and transparency to advance Healthy Choices, and to Take Action to eliminate contributors to cancer. We aim to make least-toxic options the norm.

Recent decades have seen a progression of thought as to ethical, effective decision-making, starting with the Precautionary Principle consensus statement in 1998:1

When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically.

Absolute proof that a toxicant causes harms may take a generation or more. Adoption of the Precautionary Principle reduces delays in actions, and avoids great costs to public health.

In 2007, the Swedish Chemicals Agency (KEMI) proposed operationalizing using the Substitution Principle as described in 2007:2

If risks to the environment and human health and safety can be reduced by replacing a chemical substance or product either by another substance or by some non-chemical technology, then this replacement should take place. All decisions on such substitutions should be based on the best available evidence. This evidence can be sufficient to warrant a substitution even if quantitative risk estimates cannot be made.

as modernized with the Concept of Essential Use or essentiality to regulate groups of chemicals:3

To assess the essentiality of a particular use case, three considerations need to be addressed:

1. the function (chemical, end use and service) that the chemical provides in the use case,
2. whether the function is necessary for health and safety and critical for the functioning of society and
3. if the function is necessary, whether there are viable alternatives for the chemical for this particular use.

Clearly cancer ranks among many consequences of heat, drought, fires, crop failures and ecological collapse, whereas human and environmental health reap many benefits from measures for a lower-carbon, less-polluted, sustainable, resilient future. Prevent Cancer Now applies a “Climate Lens” to all science for cancer prevention.


  1. Kriebel D, Tickner J, Epstein P, Lemons J, Levins R, Loechler EL, et al. The precautionary principle in environmental science. Environ Health Perspect. 2001 Sep;109(9):871–6.
  2. Swedish Chemicals Agency (KEMI). The Substitution Principle. Stockholm; 2007. Report No.: 8/07.
  3. Cousins IT, De Witt JC, Glüge J, Goldenman G, Herzke D, Lohmann R, et al. Finding essentiality feasible: common questions and misinterpretations concerning the “essential-use” concept. Environ Sci Process Impacts. 2021 Jun;23(8):1079–87.
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