Compositional and structural analysis of engineered stones and inorganic particles in silicotic nodules of exposed workers

Table 1 Percentages of crystalline phases measured by XRD, atomic percentage of more often elements measured by XRF, and trace elemental analyses of specific metal species by ICP-MS

Sample/method	M1	M2	M3	M4	M5	M6	M7
XRD (cryst. %)	2% Qu 98% Cri	25% Qu 45% Cri 30% Alb	100% Cri	53% Qu 47% Cri	56% Qu 44% Cri	100% Qu	100% Qu
XRF at. %*	66.6 O 32.7 Si 0.5 Ti	64.5 O 29.3 Si 3.3 Na 2.5 Al 0.2 Ti 0.1 Ca	66.7 O 32.7 Si 0.6 Ti	66.6 O 33.2 Si 0.1 Ti	66.7 O 33.2 Si	66.6 O 32.9 Si 0.3 Ti	64.4 O 30.4 Si 3.3 Na 1.4 Ca 0.1 Mg
ICP (mg/kg)**
As	< 0.2	< 0.2	< 0.2	< 0.2	< 0.2	< 0.2	< 0.2
Cd	0.014	0.007	0.006	< 0.003	< 0.003	0.006	0.015
Co	42.2	62.4	29	127	102	75	71.3
Cu	4.93	13	5.30	98.1	50.2	58	96.0
Ni	5.21	9.1	3.21	21.6	16.4	12	12.4
Pb	1.1	1.95	1.2	0.53	0.66	2.21	409
Zn	3	20.5	6.56	256	59.5	228	312
Ba	24	16	25	11	10.3	13.4	262
Mo	0.222	0.251	0.204	0.385	7.44	0.280	0.413
Sb	0.151	0.150	0.154	0.150	0.170	0.154	0.413
V	0.971	1.72	0.870	0.592	208	0.830	2.20
Ti	8992	2861	9527	1067	691	4228	614
Al	1730	43,000	1622	1439	1900	1755	536
Ca	124	3188	115	152	169	143	45,546
Na	1913	30,250	2054	1216	1437	351	38,281
Fe	250	334	235	506	400	523	670
W	281	564	156	1221	1015	695	705

^*Measurements < 0.1% have been discarded
^**Limits of detection (mg/kg): As = 0.2, Cd = 0.003, Co = 0.230 Cu = 0.120, Ni = 0.084, Pb = 0.240, Zn = 0.580, Ba = 0.360, Mo = 0.130, Sb = 0.060, V = 0.130, Al = 100, Fe = 10, Ca = 20, Na = 110, Ti = 4, W = 30
Qu quartz, Cri cristobalite, Alb albite, XRD X-ray diffraction, XRF X-ray fluorescence, ICP Inductively coupled plasma

ISSN: 1743-8977