Biological Impact of Exposure to Extremely Fine-Grained Volcanic Ash

Table 2

Chemical composition expressed as mass percent of major elements of 100 ash particles from the ash samples of the 5th of October 1999 eruption of the PVC (see Table S1 for details).

Element	Na	Mg	Al	Si	P	S	K	Ca	Ti	Mn	Fe
Mean value	5.07	1.76	17.29	43.83	1.52	2.42	5.11	10.02	2.34	0.16	10.49
Sigma	2.60	3.08	4.95	9.67	1.26	4.48	2.63	5.72	7.62	0.16	10.65
Sigma mean	0.26	0.31	0.49	0.97	0.13	0.45	0.26	0.57	0.76	0.02	1.06