Conductivity
Cities measured
87
Detected in
87 / 87
EU limit
2500 μS/cm
Highest
1242 μS/cm — Abu Dhabi
Overview
Electrical conductivity reflects the total concentration of dissolved ions (minerals) in water. Higher conductivity means more dissolved solids (TDS). Stockholm's soft granite-bedrock water has relatively low conductivity (150–400 μS/cm) compared to hard-water cities drawing from limestone aquifers.
Health Relevance
Conductivity is not a direct health parameter. Very low conductivity (< 30 μS/cm) may indicate demineralised water lacking essential minerals. Very high (> 2500 μS/cm) signals problematic salt concentrations.
Regulatory Limits
Drinking Water Directive 2020/2184
2500 μS/cm at 20°C (indicator — taste and corrosion)
Controversy & Contested Science
High-end mineral water brands equate high TDS with health and quality. Conversely, reverse osmosis (RO) filter companies market near-zero TDS water as 'pure'. WHO guidance states there is 'no convincing evidence' of health risks at TDS < 1000 mg/L. Some researchers argue very low-mineral water may impair dietary calcium and magnesium absorption — a concern when RO-filtered water replaces mineral-rich food sources for vulnerable populations.