Table 10.

Levels of heavy metals in the soil and sandpits in playgrounds (mg kg^-1)

	Cd	Cr	Cu	Ni	Pb	Zn
Soils—this study	4,6	192.2	19.2	11.7	47.4	90.3
Soils (under swings)—this study	5.1	209.3	17.5	13.8	40.2	97.5
Sandboxes—this study	4.5	177.8	11.4	13.6	32.0	52.6
Sandboxes1 (Kicińska 2018)	0.04	49	64	36	87	189
Sandboxes2 (Jasiewicz et al. 2009)	0.08	2.3	1.3	1.7	13.7	66
Soils2 (Nieć et al. 2013)	0.2–3.2	–	–	–	77–115	81–521
Sandy soils3 (De Miguel et al. 2007)	0.14	17	14	5.7	22	50
Soils4—urban parks (Kicińska 2016)	–	–	–	–	71–341	38–244
Sandboxes4—urban parks (Kicińska 2016)	–	–	–	–	28–36	17–103
Soils5 (Verla et al. 2015)	0.7	12.8	26.5	20.3	6.0	62.5

¹< 63 μm, ²unknown fraction, ³< 100 μm, ⁴< 2000 μm, ⁵< 200 μm