MANILA — Las Piñas' 28-year-old congressional aspirant Barry Tayam - who may be the youngest among those who filed their certificates of candidacy (COC) for NCR district representative - has tested negative for illegal substances.

This, as he took on the challenge of Vice President Sara Duterte to congressional bets to undergo a drug test.

"Dahil ako po yung pinakabatang congressional district representative aspirant sa buong Metro Manila, and I accept po yung challenge ni VP Duterte na dapat mag pa drug test yung mga young guns sa Congress pati na rin po mga aspirant," he told ABS-CBN News in a message.

"As part of the youth, responsibilidad ko rin po na maging role model di lang po sa kabataan pati na rin po sa lahat ng kandidato. Wala naman po mali sa sinabi ni VP Duterte, karapatan po ng mga constituents namin na ma assure na drug free ang congress pati narin po yung mga tumatakbo. And I really admire po Cong. Nograles at lahat po ng tumanggap ng hamon na 'to," he added.

Tayam, a Senior High School teacher, will be up against Sen. Cynthia Villar, Las Piñas Councilor Mark Anthony Santos; and another teacher, Professor Luisito Redoble.

On Tuesday, Duterte challenged congressional aspirants to undergo neuro-psychiatric and drug tests, in response to calls from some lawmakers for her to undergo a neuro-psychiatric exam or have her mental health evaluated.

Duterte said that at any time, and even televised, she is ready to take a neuro-psychiatric test - as long as she is not the only one who will undergo this.

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