diff --git a/monitor/backend.go b/monitor/backend.go
index edf956d..218c7c2 100644
--- a/monitor/backend.go
+++ b/monitor/backend.go
@@ -81,7 +81,7 @@ func (mms *MqttMonitor) CleanupDB() {
 	defer iter.Release() // Make sure to release the iterator at the end
 
 	// Iterate over all elements in the database
-	for iter.Next() {
+	for iter.Next() && !mms.IsTerminated() {
 		// Use iter.Key() and iter.Value() to access the key and value
 		lastSeen, err := mms.getDataFromIter(iter)
 		if err != nil {
diff --git a/monitor/interface.go b/monitor/interface.go
index 7e5d6e0..4e73171 100644
--- a/monitor/interface.go
+++ b/monitor/interface.go
@@ -1,6 +1,8 @@
 package monitor
 
 import (
+	"sync"
+
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/planetmint/planetmint-go/config"
 	"github.com/syndtr/goleveldb/leveldb"
@@ -13,10 +15,20 @@ type MQTTMonitorClientI interface {
 	Start() (err error)
 }
 
-var MqttMonitorInstance MQTTMonitorClientI
+var monitorMutex sync.Mutex
+var mqttMonitorInstance MQTTMonitorClientI
+
+func SetMqttMonitorInstance(monitorInstance MQTTMonitorClientI) {
+	monitorMutex.Lock()
+	mqttMonitorInstance = monitorInstance
+	monitorMutex.Unlock()
+}
 
 func LazyMqttMonitorLoader(homeDir string) {
-	if MqttMonitorInstance != nil {
+	monitorMutex.Lock()
+	tmpInstance := mqttMonitorInstance
+	monitorMutex.Unlock()
+	if tmpInstance != nil {
 		return
 	}
 	if homeDir == "" {
@@ -26,9 +38,37 @@ func LazyMqttMonitorLoader(homeDir string) {
 	if err != nil {
 		panic(err)
 	}
-	MqttMonitorInstance = NewMqttMonitorService(aciveActorsDB, *config.GetConfig())
-	err = MqttMonitorInstance.Start()
+	monitorMutex.Lock()
+	mqttMonitorInstance = NewMqttMonitorService(aciveActorsDB, *config.GetConfig())
+	monitorMutex.Unlock()
+	err = mqttMonitorInstance.Start()
 	if err != nil {
 		panic(err)
 	}
+
+}
+
+func SetContext(ctx sdk.Context) {
+	monitorMutex.Lock()
+	mqttMonitorInstance.SetContext(ctx)
+	monitorMutex.Unlock()
+}
+
+func SelectPoPParticipantsOutOfActiveActors() (challenger string, challengee string, err error) {
+	monitorMutex.Lock()
+	challenger, challengee, err = mqttMonitorInstance.SelectPoPParticipantsOutOfActiveActors()
+	monitorMutex.Unlock()
+	return
+}
+
+func Start() (err error) {
+	err = mqttMonitorInstance.Start()
+	return
+}
+
+func AddParticipant(address string, lastSeenTS int64) (err error) {
+	monitorMutex.Lock()
+	err = mqttMonitorInstance.AddParticipant(address, lastSeenTS)
+	monitorMutex.Unlock()
+	return
 }
diff --git a/monitor/mqtt_monitor.go b/monitor/mqtt_monitor.go
index f408292..c3830b5 100644
--- a/monitor/mqtt_monitor.go
+++ b/monitor/mqtt_monitor.go
@@ -26,6 +26,21 @@ type MqttMonitor struct {
 	numberOfElements            int64
 	sdkContext                  *sdk.Context
 	contextMutex                sync.Mutex
+	isTerminated                bool
+	terminationMutex            sync.Mutex
+}
+
+func (mms *MqttMonitor) Terminate() {
+	mms.terminationMutex.Lock()
+	mms.isTerminated = true
+	mms.terminationMutex.Unlock()
+}
+
+func (mms *MqttMonitor) IsTerminated() (isTerminated bool) {
+	mms.terminationMutex.Lock()
+	isTerminated = mms.isTerminated
+	mms.terminationMutex.Unlock()
+	return
 }
 
 func LazyLoadMonitorMQTTClient() {
@@ -115,6 +130,9 @@ func (mms *MqttMonitor) SelectPoPParticipantsOutOfActiveActors() (challenger str
 }
 
 func (mms *MqttMonitor) MqttMsgHandler(_ mqtt.Client, msg mqtt.Message) {
+	if mms.IsTerminated() {
+		return
+	}
 	topicParts := strings.Split(msg.Topic(), "/")
 	if len(topicParts) != 3 {
 		return
@@ -153,7 +171,7 @@ func (mms *MqttMonitor) MqttMsgHandler(_ mqtt.Client, msg mqtt.Message) {
 
 func (mms *MqttMonitor) MonitorActiveParticipants() {
 	LazyLoadMonitorMQTTClient()
-	for {
+	for !mms.IsTerminated() {
 		if !MonitorMQTTClient.IsConnected() {
 			if token := MonitorMQTTClient.Connect(); token.Wait() && token.Error() != nil {
 				mms.Log("[Monitor] error connecting to mqtt: " + token.Error().Error())
@@ -169,7 +187,7 @@ func (mms *MqttMonitor) MonitorActiveParticipants() {
 				panic(token.Error())
 			}
 		}
-		time.Sleep(30 * time.Second)
+		time.Sleep(5 * time.Second)
 	}
 }
 
diff --git a/monitor/mqtt_monitor_test.go b/monitor/mqtt_monitor_test.go
index ff868ed..7033f4a 100644
--- a/monitor/mqtt_monitor_test.go
+++ b/monitor/mqtt_monitor_test.go
@@ -44,6 +44,7 @@ func TestGMonitorActiveParticipants(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Contains(t, challenger, "plmnt")
 	assert.Contains(t, challengee, "plmnt")
+	mqttMonitor.Terminate()
 }
 
 func TestCleanupRemoval(t *testing.T) {
@@ -71,6 +72,7 @@ func TestCleanupRemoval(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, "", challenger)
 	assert.Contains(t, "", challengee)
+	mqttMonitor.Terminate()
 }
 
 func TestCleanupPrecisionTest(t *testing.T) {
@@ -99,4 +101,5 @@ func TestCleanupPrecisionTest(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Contains(t, challenger, "plmnt")
 	assert.Contains(t, challengee, "plmnt")
+	mqttMonitor.Terminate()
 }
diff --git a/tests/e2e/dao/pop/selection_suite.go b/tests/e2e/dao/pop/selection_suite.go
index 3a1b25a..60c061e 100644
--- a/tests/e2e/dao/pop/selection_suite.go
+++ b/tests/e2e/dao/pop/selection_suite.go
@@ -166,7 +166,7 @@ func (s *SelectionE2ETestSuite) TestPopSelectionNoActors() {
 func (s *SelectionE2ETestSuite) TestPopSelectionOneActors() {
 	err := e2etestutil.AttestMachine(s.network, machines[0].name, machines[0].mnemonic, 0, s.feeDenom)
 	s.Require().NoError(err)
-	err = monitor.MqttMonitorInstance.AddParticipant(machines[0].address, time.Now().Unix())
+	err = monitor.AddParticipant(machines[0].address, time.Now().Unix())
 	s.Require().NoError(err)
 
 	out := s.perpareLocalTest()
@@ -178,7 +178,7 @@ func (s *SelectionE2ETestSuite) TestPopSelectionOneActors() {
 func (s *SelectionE2ETestSuite) TestPopSelectionTwoActors() {
 	err := e2etestutil.AttestMachine(s.network, machines[1].name, machines[1].mnemonic, 1, s.feeDenom)
 	s.Require().NoError(err)
-	err = monitor.MqttMonitorInstance.AddParticipant(machines[1].address, time.Now().Unix())
+	err = monitor.AddParticipant(machines[1].address, time.Now().Unix())
 	s.Require().NoError(err)
 
 	out := s.perpareLocalTest()
diff --git a/testutil/keeper/dao.go b/testutil/keeper/dao.go
index 1c40f20..9e32731 100644
--- a/testutil/keeper/dao.go
+++ b/testutil/keeper/dao.go
@@ -24,7 +24,7 @@ import (
 )
 
 func DaoKeeper(t testing.TB) (*keeper.Keeper, sdk.Context) {
-	monitor.MqttMonitorInstance = &monitormocks.MockMQTTMonitorClientI{}
+	monitor.SetMqttMonitorInstance(&monitormocks.MockMQTTMonitorClientI{})
 	storeKey := sdk.NewKVStoreKey(types.StoreKey)
 	memStoreKey := storetypes.NewMemoryStoreKey(types.MemStoreKey)
 	challengeStoreKey := storetypes.NewMemoryStoreKey(types.ChallengeKey)
diff --git a/testutil/network/loader.go b/testutil/network/loader.go
index ea5ac72..028aaaf 100644
--- a/testutil/network/loader.go
+++ b/testutil/network/loader.go
@@ -42,7 +42,7 @@ func Load(t *testing.T, configs ...Config) *Network {
 	// use mock client for testing
 	util.MQTTClient = &mocks.MockMQTTClient{}
 	monitor.MonitorMQTTClient = &mocks.MockMQTTClient{}
-	monitor.MqttMonitorInstance = &monitormocks.MockMQTTMonitorClientI{}
+	monitor.SetMqttMonitorInstance(&monitormocks.MockMQTTMonitorClientI{})
 	elements.Client = &elementsmocks.MockClient{}
 	util.RegisterAssetServiceHTTPClient = &mocks.MockClient{}
 
diff --git a/x/dao/abci.go b/x/dao/abci.go
index 0b1ff0a..49680f0 100644
--- a/x/dao/abci.go
+++ b/x/dao/abci.go
@@ -24,8 +24,8 @@ func BeginBlocker(ctx sdk.Context, req abci.RequestBeginBlock, k keeper.Keeper)
 	hexProposerAddress := hex.EncodeToString(proposerAddress)
 	if isPopHeight(ctx, k, currentBlockHeight) {
 		// select PoP participants
-		monitor.MqttMonitorInstance.SetContext(ctx)
-		challenger, challengee, err := monitor.MqttMonitorInstance.SelectPoPParticipantsOutOfActiveActors()
+		monitor.SetContext(ctx)
+		challenger, challengee, err := monitor.SelectPoPParticipantsOutOfActiveActors()
 		if err != nil {
 			util.GetAppLogger().Error(ctx, "error during PoP Participant selection ", err)
 		}