Mentha oil futures for February fell by Rs 25.10, or 1.64% to Rs 1,500 per kg in 80 lots.At the Multi Commodity Exchange (MCX), the March contract traded Rs 19.10, or 1.46% lower at Rs 1,283 per kg in 683 lots.Prices fell as speculators indulged in profit-booking at existing higher levels.Subdued domestic demand also affected the trade.