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	Annual Toxics Summary Azusa FAQs Benzene parts per billion

Read About Estimated Risk

Year	Months Present	Minimum	Median	Mean	90th Percentile	Maximum	Standard Deviation	Number of Observations	Detection Limit	Estimated Risk
2025		*	*	*	*	*	*	0	*	*
2024		*	*	*	*	*	*	0	*	*
2023		*	*	*	*	*	*	0	*	*
2022		0.06	0.13	*	0.23	0.31	0.06	22	0.05	*
2021		0.08	0.17	*	0.38	0.66	0.133	24	0.05	*
2020		0.11	*	*	*	0.33	0.077	7	0.05	*
2019		0.09	0.15	0.173	0.24	0.48	0.081	30	0.05	45
2018		0.12	0.19	0.245	0.35	1.2	0.209	31	0.05	64
2017		0.08	0.21	0.254	0.39	0.78	0.15	30	0.05	66
2016		0.1	0.26	0.308	0.58	0.82	0.17	31	0.05	80
2015		0.13	0.25	0.25	0.38	0.47	0.085	30	0.05	65
2014		0.11	0.22	0.27	0.44	0.8	0.159	30	0.05	70
2013		0.11	0.23	0.279	0.45	0.75	0.154	31	0.05	73
2012		0.14	0.28	0.30	0.43	0.53	0.101	30	0.05	78
2011		0.11	0.32	0.333	0.5	0.73	0.15	30	0.05	87
2010		0.19	0.3	0.397	0.5	1.0	0.175	24	0.05	103
2009		0.1	0.29	0.328	0.6	1.1	0.211	31	0.05	85
2008		0.18	0.3	*	0.55	0.89	0.163	28	0.05	*
2007		0.15	0.36	0.42	0.78	1.2	0.248	27	0.05	109
2006		0.16	0.37	0.376	0.52	0.83	0.152	29	0.05	98
2005		0.15	0.47	0.512	0.76	1.2	0.265	29	0.05	133
2004		0.2	0.36	0.432	0.76	1.0	0.211	29	0.05	112
2003		0.25	0.55	0.598	0.81	2.1	0.349	28	0.05	156
2002		0.29	0.55	0.621	1.13	1.5	0.332	28	0.05	161
2001		0.2	0.63	*	1.15	1.4	0.331	26	0.05	*
2000		0.3	0.6	0.69	1.0	3.1	0.51	30	0.2	180
1999		0.8	*	*	*	0.8	0.81	1	0.2	*
1998		*	*	*	*	*	*	0	*	*
1997		*	*	*	*	*	*	0	*	*
1996		*	*	*	*	*	*	0	*	*
1995		*	*	*	*	*	*	0	*	*
1994		*	*	*	*	*	*	0	*	*
1993		*	*	*	*	*	*	0	*	*
1992		*	*	*	*	*	*	0	*	*
1991		*	*	*	*	*	*	0	*	*
1990		*	*	*	*	*	*	0	*	*
1989		1.0	*	*	*	3.2	0.81	7	0.5	*

	Notes:	Values below the Limit of Detection (LoD) assumed to be ½ LoD. Means and risks shown only for years with data in all 12 months. "*" means there was insufficient or no data available to determine the value.