TABLE 2.

Compiled Si and Mg release rates from chrysotile asbestos during different chemical and biological treatments^a

Reference	Organism/medium	Temp (°C)	Initial pH	Mineral	Starting asbestos amt (g L−1)	Incubation time (days)	Initial [Si]aq (mM)	Final [Si]aq (mM)	Si release rate (mM g−1 day−1)	Initial [Mg]aq (mM)	Final [Mg]aq (mM)	Mg release rate (mM g−1 day−1)
This study	T. ammonificans/modified SME	75	5.5	Chrysotile (Balangero, Italy)	1.0	2	0.21	1.10	0.45	0.55	1.83	0.64
90	Water	25	4	Chrysotile (Thetford, Canada)	0.5	7.1	0*	1.4	0.40	0*	3.94	1.1
36	Verticillium leptobactrum/Czapek	25	5.5	Chrysotile (Balangero, Italy)	2.3	20	0*	1.9	0.04	0*	4.7	0.10
91	Sulfuric acid (0.05 M) (used highest values in Table 3 of the reference)	25	1.3	Chrysotile (Málaga, Spain)	2.0	30	0*	1.9	0.03	0*	22	0.37
91	Oxalic acid (0.2 M) (used highest values in Table 4 of the reference)	25	1.2	Chrysotile (Málaga, Spain)	2.0	30	0*	1.2	0.02	0*	21	0.35
91	Nitric acid (0.1 M) (used highest values in Table 2 of the reference)	25	1.2	Chrysotile (Málaga, Spain)	2.0	30	0*	1.4	0.02	0*	17	0.28
90	Water	25	9	Chrysotile (Thetford, Canada)	0.5	7.1	0*	0.044	0.01	0*	0.18	0.05
36	Fusarium oxysporum/Czapek	25	5.5	Chrysotile (Balangero, Italy)	2.3	20	0*	0.3	0.007	0*	2.4	0.05
90	Water	25	7	Chrysotile (Thetford, Canada)	0.5	43	0*	0.1	0.005	0*	0.42	0.02

^aData are organized by decreasing Si release rates. Si and Mg release rates are provided as millimolar concentrations per gram of chrysotile initially provided per day. Initial dissolved [Si] and [Mg] marked with an asterisk are assumed values, as data are not available from the reference. Note that chrysotile incubations in modified SME medium in the absence of T. ammonificans yielded Si and Mg release rates similar to those reported in this table. Data obtained in this study and values for Si and Mg release rates are shaded.