let params = {
    ExpressionAttributeValues:{
        ":v1": {
            S: event.email
        }
    },
    KeyConditionExpression: "email = :v1",
    ProjectionExpression: "password",
    TableName: process.env.DynamoName
};

dynamo.query(params, (err,data) => {
    if(err) console.log('err',err);
    else console.log('pass',data.Items[0].password);
})

{
  Items:
    [ { password: [Object] } ],
  Count: 1,
  ScannedCount: 1
}