SQL & PL/SQL

I am trying to find rows from a table which has unexpected records. for that i have created a exception table..

Table Name = ABC

TABLE_NAME	COLsUMN_NAME	COL_VALUES
------------	-----------	-----------
CUSTOMER	DEPARTMENT	0
CUSTOMER	DEPARTMENT	NULL

It says, if Department column of Customer table contains value 0 or NULL, notify concerned team. There are many other tables on which we need to perform same.

I have created a procedure which will run after daily load.

CREATE OR REPLACE PROCEDURE EXCP_TEST
AS


BEGIN
	FOR TableList IN (SELECT DISTINCT TABLE_NAME FROM ABC)
	LOOP
		FOR ColumnList IN (SELECT COLUMN_NAME, COL_VALUES FROM ABC WHERE TABLE_NAME = TableList.TABLE_NAME)
		LOOP
			/* below code will create dynamic WHERE Condition. (as NULL requires Column_name 'IS NULL' and other value requires columna_name = '0' */

			IF ColumnList.COL_VALUES = 'NULL'
			THEN
				v_where = ' IS NULL ';
			ELSE
				v_where := ' = ' ||''''||ColumnList.COL_VALUE||'''';
			END IF;

			/* below code is to check if any record exists. Here is an issue. WHile executing Dynamic SQL it gives an error. */
			/* Error is : Invalid relational Operator

			EXECUTE IMMEDIATE 'SELECT COUNT(1) FROM ' || v_tabname || ' WHERE ' || v_colname  || ' :a ' into v_cnt using v_where;
		END LOOP
	END LOOP;
END;

Can comeone help me to find solution for the same...?