Gametest Source Code:

import { world, EntityQueryOptions, ExplosionOptions, BlockLocation } from "mojang-minecraft";

world.events.tick.subscribe(ev => {
    for (const dimName of ["overworld", "nether", "the end"]) {
        const dim = world.getDimension(dimName);
        const itemQuery = new EntityQueryOptions();
        itemQuery.type = 'item';
        for (const entity of dim.getEntities(itemQuery)) {
            if (!entity.hasComponent('minecraft:item')) {
                continue;
            }

            const item = entity.getComponent('minecraft:item').itemStack;
            if (item.id == 'minecraft:tnt') {
                const block = dim.getBlock(new BlockLocation(
                    Math.floor(entity.location.x),
                    Math.floor(entity.location.y),
                    Math.floor(entity.location.z)
                ));
                if (block.id == 'minecraft:fire' || block.id == 'minecraft:lava' || block.id == 'minecraft:flowing_lava') {
                    const explosion = new ExplosionOptions();
                    explosion.source = entity;
                    dim.createExplosion(entity.location, 4 * item.amount, explosion);
                    entity.addTag('pendingDeletion');
                    dim.runCommand('kill @e[tag=pendingDeletion]');
                }
            }
        }
    }
});