| Serial number | Country | Region | Groundwater As level (ppb) | Permissible limit (ppb) | References |
| 1 | Afghanistan | Ghazni | 10–500 | 10 (WHO) | [21] | 2 | Australia | Victoria (around the gold-mining regions) | 1–12 (Groundwater); 1–73 (Drinking-water); 1–220 (Surface water) | — | [17, 21, 216] | 3 | Bangladesh | Noakhali | <1–4730 | 50 (WHO) | [18, 21, 217] | 4 | Brazil | Minas Gerais (Southeastern Brazil) | 0.4–350 (Surface water) | 10 (WHO) | [17, 216, 218] | 5 | Cambodia | Prey Veng and Kandal-Mekong delta | Up to 900 1–1610 | 10 (WHO) | [20, 21] | 6 | Canada | Nova Scotia (Halifax county) | 1.5–738.8 | 10 (WHO) | [17, 21] | 7 | China | — | 50–4440 | 50 (WHO) | [219] | 8 | Finland | Southwest Finland | 17–980 | 10 (WHO) | [17, 216, 218] | 9 | Greece | Fairbanks (mine tailings) | Up to 10,000 | 10 (WHO) | [1, 21] | 10 | India | West Bengal Uttar Pradesh | 10–3200 | 50 (WHO) | [1, 21, 216, 220, 221] | 11 | Japan | Fukuoka Prefecture (southern region) | 1–293 | 10 (WHO) | [17, 216] | 12 | Mexico | Lagunera | 8–620 | 25 | [1, 21, 216] | 13 | Nepal | Rupandehi | Up to 2620 | 50 | [21, 219, 222] | 14 | Pakistan | Muzaffargarh (southwestern Punjab) | Up to 906 | 50 | [17, 22, 216] | 15 | Taiwan | — | 10–1820 | 10 (WHO) | [1, 21, 216] | 16 | Thailand | Ron Phibun | 1–>5000 | 10 (WHO) | [1, 21, 216] | 17 | USA | Tulare Lake | Up to 2600 | 10 (USEPA) | [21, 24, 223] | 18 | Vietnam | Red River Delta (Northern Vietnam) Mekong Delta (Southern Vietnam) | <1–3050 | 10 (WHO) | [1, 219] |
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