Discuss the distinction between 'hazard identification' and 'risk assessment' in IARC's carcinogen classification, and its implications for public health communication in India.

The IARC Monographs Preamble draws a sharp line: hazard is the strength of evidence that an agent can cause cancer, while risk is the probability that a given exposure will do so [1]. IARC identifies hazards only; it does not quantify risk — a distinction routinely lost in public reporting.

Hazard identification: what IARC actually does

• Working Groups weigh human, animal and mechanistic evidence to judge whether an agent is capable of causing cancer, sorting agents into Group 1 (carcinogenic) to Group 3 (not classifiable) [1].
• Groups reflect certainty of evidence, not potency or dose — tobacco and processed meat share Group 1 despite vastly different real-world burdens [2].
• Volume 137 (2026) placed hydrochlorothiazide, voriconazole and tacrolimus in Group 1 [3].

Risk assessment: what IARC does not do

• Exposure-response characterisation, dose thresholds and population attributable burden lie outside the Monographs' remit [1].
• These belong to national regulators and clinicians, who weigh benefit against harm for a specific patient.

Implications for communication in India

• All three drugs are on the WHO Model List of Essential Medicines, adopted in over 150 countries [4]; a "cancer-causing medicine" headline risks mass self-discontinuation of antihypertensives and transplant immunosuppressants — harms far exceeding the flagged hazard.
• India's high hypertension burden and low health literacy amplify panic; risk is also unevenly distributed, as sun-exposed rural, coastal and hilly populations face higher skin-cancer risk from hydrochlorothiazide [3].
• Institutional follow-through matters: CDSCO must update labelling and monitoring guidance, and the Pharmacovigilance Programme of India (PvPI) must convert signals into evidence-based advisories rather than leaving the field to rumour [5].

Hazard classification is the beginning of a policy conversation, not its verdict. India's response should pair prompt regulatory review with plain-language advisories that state the hazard honestly while urging patients not to stop treatment without medical advice — translating global science into calibrated, trust-preserving communication in the spirit of the right to health under Article 21.