ALTER TABLE `bs`.`waste`
    ADD itemFk INT NULL AFTER `family`;

ALTER TABLE `bs`.`waste`
    ADD itemTypeFk SMALLINT(5) UNSIGNED NULL AFTER `itemFk`;

ALTER TABLE `bs`.`waste`
    ADD CONSTRAINT waste_itemType_id
        FOREIGN KEY (itemTypeFk) REFERENCES vn.itemType (id)
            ON UPDATE CASCADE;

ALTER TABLE `bs`.`waste`
    ADD CONSTRAINT waste_item_id
        FOREIGN KEY (itemFk) REFERENCES vn.item (id)
            ON UPDATE CASCADE;