The Parkinson’s-stricken son of Brooke Astor landed in a maximum-security lockup Wednesday, The Post has learned.

The harrowing assignment was not because of the risk he poses, but rather because the Hudson Valley prison was the closest jail with adequate health care for 89-year-old Anthony Marshall, sources said.

Downstate Correctional Facility is notorious for its high suicide rate, with the fifth highest of all state prisons — 10 since 2010.

A 2011 report by the state Commission of Correction called for an investigation into the prison, which caters to disabled jailbirds.

Marshall swiped millions from his philanthropist mom to pad his already cushy lifestyle with a $2 million bonus, a 55-foot yacht and upkeep for a Maine estate.

The wheelchair-bound convict is serving one to three years. His first parole hearing is in December.