Table 1 Occupational Health and Safety: Strategies for prevention of exposure to toxic materials and hazardous conditions in ASM are classified as primordial, primary, secondary, and tertiary

Primordial prevention: Actions designed to prevent dangerous exposures from ever occurring.

Examples: Removal of mercury from Artisanal and Small-Scale Gold Mining.

Primary prevention: Strategies for preventing disease by reducing exposures.

Examples: Controlling workplace exposures to metals through process enclosure, exhaust ventilation, administrative controls, and personal protective equipment. While important, these measures are less effective than outright bans or substitution with less hazardous materials. Their application is guided by the Hierarchy of Controls framework (see below).

Standard-setting is an important aspect of primary prevention of exposure to toxic metals. In most countries, standard-setting is a legal as well as a scientific process and is often guided by the paradigm of Risk Assessment and Risk Management. Risk assessment/risk management is sometimes modified by application of the Precautionary Principle [1,2,3].

Secondary prevention: Methods for early detection of disease before the appearance of symptoms, complications, or spread, through biological monitoring and health surveillance.

Example: Blood lead and urinary mercury screening to detect exposures leading to biochemical changes related to minimal or slight symptoms [4, 5]. Biochemical analyses of precursors of symptoms or slight symptoms, e.g. erythrocyte zinc protoporphyrin in occupational lead exposure [5].

Tertiary prevention: Methods to prevent severe consequences of disease, such as disability or death.

Examples: Chelation therapy of acute, high-dose exposures to metals [6].

Application of this classification of preventive strategies to the prevention of occupational exposures in ASM is guided by the “Hierarchy of Controls” framework, developed by the US National Institute for Occupational Safety and Health.

Figure 1: National Institute for Occupational Safety and Health (NIOSH). Hierarchy of controls [Internet]. Centers for Disease Control and Prevention. Centers for Disease Control and Prevention; 2015. Available from: https://www.cdc.gov/niosh/topics/hierarchy/default.html

Minimizing or eliminating exposures at the source before exposure ever occurs—primordial prevention—is the single most effective and cost-effective means of preventing hazardous exposures. It is therefore listed first in the hierarchy of controls. Personal protective equipment (PPE), while very important, is the least effective of these control strategies and thus is listed last.

Insufficient training and education is a pervasive problem in ASM. Miners are often unaware of the hazards, which are largely shaped by the social and communal setting and influenced by informal or illegal working situations and a lack of OHS management organizations. Evaluation of the few OHS programs in ASM has not been undertaken but would be crucial. Long-term consequences of hazard exposure are not researched sufficiently and analogous legislation and regulation in the field of ASM lack attention and are low on the political agenda [7,8,9].