Table 6.

Comparison of the heavy metal levels in this study with other national and international studies.

Country	Studied water source	Brands	Sample count	Heavy metal Concentration range (μg/L)					Ref.
				Cr	Cd	Pb	Ni	As
Iran (this study)	Bottled water (tap)	11	33	5–34	1.5–2.5	1–7	2–29	0–3.5	–
Romania (2022)	Bottled water (mineral)	50	50	<0.10–4.02	<0.09–<0.09	<0.07–6.0	0.16–3.77	–	[41]
Nigeria (2018)	Bottled water,	20	N/A	ND	<LOD – 72.1	<LOD – 348.1	<LOD – 12.4	–	[30]
Italy (2018)	Spring, mineral, tap water	N/A	46	–	0.0008–0.0024	0.006–0.104	–	–	[42]
Iran (2015)	Bottled water (mineral & tap)	42	128	–	0.6–1.5	3–7.6	–	3.1–526.6	[33]
Sari, Iran (2015)	Bottled water (tap)	15	60	10–49	<LOD – 0.1	<LOD – 13.7	<LOD – 31	<LOD – 0.5	[40]
Bandar Abbas, Iran (2015)	Bottled water (tap)	8	432	–	0–7.1	–	–	–	[45]
Turkey (2013)	Bottled water	17	N/A	–	ND	ND – 0.013	–	ND – 0.011	[39]
	Tap water	–	78	–	ND	ND – 4.82	–	ND
Dehli, India (2014)	Sachet water (tap)	N/A	16	ND	–	30–329	–	–	[43]
	Bottled water (tap)	N/A	4	<LOD - 16	–	<LOD - 58	–	–
Nepal (2020)	Bottled water (tap)	N/A	100	–	ND	ND	0.8–23		[46]
Kampala, Uganda (2017)	Tap water	8	24	ND – 34	ND	17–310	ND - 170	5–14	[44]
	Spring water	12	36	ND – 98	ND	105–412	ND - 373	8–14
	Bottled water (tap)	9	27	ND – 107	ND		ND	ND
Serbia (2011)	Bottled water (mineral)	16	16	<0.21–1.51	<0.01–0.18	<0.04–1.06	<0.30–8.38	<0.20–6.32	[38]
	Bottled water (spring)	7	7	<0.21–1.57	<0.01–0.36	0.21–0.91	<0.30–3.52	<0.20–6.06
	Tap water	4	4	0.25–0.58	0.08–1.19	0.33–2.89	0.90–1.82	2.20–6.41
Khorram-Abad, Iran (2018)	Tap water	45	45	0.6–10.6	0.02–1.49	0.35–8.27	–	–	[28]
Rafsanjan, Iran (2021)	Well and tap water	23	23	1.02–10.53	0.51–1.66	4.12–33.42	–	7.02–102.22	[29]
Saravan, Iran (2021)	Well	89	89	0.49–20	0.11–12.8	0.1–36.02	–	–	[37]
Kurdistan province, Iran (2021)	Well	138	138	0.1–53	0.1–0.2	0.2–14.3	0.1–5.3	1–54	[25]
Yazd, Iran (2017)	Bottled water (tap)	2	2	–	<0.2 (Brand 1) <0.2 (Brand 2)	3.2 (Brand 1) 3.1 (Brand 2)	1.3 (Brand 1) 4.1 (Brand 2)	–	[31]