Forensic Medicine Toxicology - 1 0cdf2265 The earliest markers of renal injury in lead poisoning is the:- A Elevated lead level in urine B Elevated free protoporphyrin in urine C Elevated b 2 microglobulin in urine D Elevated coproporphyrin in urine High-Yield Explanation Elevated urinary levels of N-acetyl-3-D-glucosaminidase and b-2-microglobulin may serve as early markers of renal injury.