How many inspections done in 2010 had serious food safety issue?
in 2010 refers to inspection_date like '2010%'; had serious food safety issue refers to risk_level = 3
SELECT COUNT(T2.inspection_id) FROM establishment AS T1 INNER JOIN inspection AS T2 ON T1.license_no = T2.license_no WHERE strftime('%Y', T2.inspection_date) = '2010' AND T1.risk_level = 3